[llvm] Reland [SPIR-V] Support `SPV_INTEL_int4` extension (PR #141279)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-expensive-checks-ubuntu` running on `as-builder-4` while building `llvm` at step 7 "test-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/187/builds/6154

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 7 (test-check-all) failure: Test just built components: check-all completed (failure)
...
PASS: LLVM :: CodeGen/SPIRV/capability-Int64Atomics.ll (20812 of 62695)
PASS: LLVM :: CodeGen/SPIRV/decoration-order.ll (20813 of 62695)
PASS: LLVM :: CodeGen/SPIRV/branching/switch-range-check.ll (20814 of 62695)
PASS: LLVM :: CodeGen/SPIRV/const-composite.ll (20815 of 62695)
PASS: LLVM :: CodeGen/SPIRV/basic_int_types.ll (20816 of 62695)
PASS: LLVM :: CodeGen/SPIRV/capability-kernel.ll (20817 of 62695)
PASS: LLVM :: CodeGen/SPIRV/capability-Shader.ll (20818 of 62695)
PASS: LLVM :: CodeGen/SPIRV/constant/local-aggregate-constant.ll (20819 of 62695)
PASS: LLVM :: CodeGen/SPARC/float.ll (20820 of 62695)
XPASS: LLVM :: CodeGen/SPIRV/constant/local-arbitrary-width-integers-constants-type-promotion.ll (20821 of 62695)
******************** TEST 'LLVM :: CodeGen/SPIRV/constant/local-arbitrary-width-integers-constants-type-promotion.ll' FAILED ********************
Exit Code: 0

Command Output (stderr):
--
/home/buildbot/worker/as-builder-4/ramdisk/expensive-checks/build/bin/llc -O0 -mtriple=spirv32-unknown-unknown /home/buildbot/worker/as-builder-4/ramdisk/expensive-checks/llvm-project/llvm/test/CodeGen/SPIRV/constant/local-arbitrary-width-integers-constants-type-promotion.ll -o - | /home/buildbot/worker/as-builder-4/ramdisk/expensive-checks/build/bin/FileCheck /home/buildbot/worker/as-builder-4/ramdisk/expensive-checks/llvm-project/llvm/test/CodeGen/SPIRV/constant/local-arbitrary-width-integers-constants-type-promotion.ll # RUN: at line 1
+ /home/buildbot/worker/as-builder-4/ramdisk/expensive-checks/build/bin/llc -O0 -mtriple=spirv32-unknown-unknown /home/buildbot/worker/as-builder-4/ramdisk/expensive-checks/llvm-project/llvm/test/CodeGen/SPIRV/constant/local-arbitrary-width-integers-constants-type-promotion.ll -o -
+ /home/buildbot/worker/as-builder-4/ramdisk/expensive-checks/build/bin/FileCheck /home/buildbot/worker/as-builder-4/ramdisk/expensive-checks/llvm-project/llvm/test/CodeGen/SPIRV/constant/local-arbitrary-width-integers-constants-type-promotion.ll

--

********************
PASS: LLVM :: CodeGen/SPIRV/capability-integers.ll (20822 of 62695)
PASS: LLVM :: CodeGen/SPIRV/branching/OpSwitchEmpty.ll (20823 of 62695)
PASS: LLVM :: CodeGen/SPIRV/basic_float_types.ll (20824 of 62695)
PASS: LLVM :: CodeGen/SPIRV/branching/OpSwitchUnreachable.ll (20825 of 62695)
PASS: LLVM :: CodeGen/SPIRV/branching/OpSwitchBranches.ll (20826 of 62695)
PASS: LLVM :: CodeGen/SPIRV/constant/local-integers-constants.ll (20827 of 62695)
PASS: LLVM :: CodeGen/SPIRV/constant/global-constants.ll (20828 of 62695)
PASS: LLVM :: CodeGen/SPIRV/builtin_vars-decorate.ll (20829 of 62695)
PASS: LLVM :: CodeGen/SPIRV/constant/local-float-point-constants.ll (20830 of 62695)
PASS: LLVM :: CodeGen/SPIRV/constant/local-null-constants.ll (20831 of 62695)
PASS: LLVM :: CodeGen/SPIRV/constant/local-bool-constants.ll (20832 of 62695)
PASS: LLVM :: CodeGen/SPIRV/branching/Two_OpSwitch_same_register.ll (20833 of 62695)
PASS: LLVM :: CodeGen/RISCV/xqccmp-push-pop-popret.ll (20834 of 62695)
PASS: LLVM :: CodeGen/SPIRV/empty-logical.ll (20835 of 62695)
PASS: LLVM :: CodeGen/SPIRV/constant/local-vector-matrix-constants.ll (20836 of 62695)
PASS: LLVM :: CodeGen/RISCV/zmmul.ll (20837 of 62695)
PASS: LLVM :: CodeGen/SPIRV/empty-opencl32.ll (20838 of 62695)
PASS: LLVM :: CodeGen/SPIRV/const-array-in-struct.ll (20839 of 62695)
PASS: LLVM :: CodeGen/SPIRV/event_no_group_cap.ll (20840 of 62695)
PASS: LLVM :: CodeGen/SPIRV/empty-opencl64.ll (20841 of 62695)
PASS: LLVM :: CodeGen/SPIRV/execution-mode-reqd_work_group_size.ll (20842 of 62695)
PASS: LLVM :: CodeGen/SPARC/ctpop.ll (20843 of 62695)
PASS: LLVM :: CodeGen/SPIRV/execution-mode-work_group_size_hint.ll (20844 of 62695)
PASS: LLVM :: CodeGen/SPIRV/assume.ll (20845 of 62695)
PASS: LLVM :: CodeGen/SPIRV/empty-module.ll (20846 of 62695)
PASS: LLVM :: CodeGen/SPIRV/extensions/SPV_INTEL_arbitrary_precision_integers.ll (20847 of 62695)
PASS: LLVM :: CodeGen/SPIRV/extensions/SPV_INTEL_bfloat16_conversion/bfloat16-conv-negative1.ll (20848 of 62695)

```

</details>

https://github.com/llvm/llvm-project/pull/141279