[llvm] [ARM, ELF] Fix access to dso_preemptable __stack_chk_guard with static relocation model (PR #70014)

[Fangrui Song via llvm-commits]

MaskRay wrote:

Rebase after test adjustment at 6ae7b735dbd50eb7ade1573a86d037a2943e679c
```
    [ARM][test] Improve stack-protector tests

    llvm/test/LTO/ARM/ssp-static-reloc.ll is more about using the static
    relocation model with "PIC Level" and unrelated to the LTO infrastructure.
    Move the test. Update stack_guard_remat.ll to clearly test "PIC Level"
    with the relevant relocation models.

 llvm/test/CodeGen/ARM/stack-guard-elf.ll   | 41 +++++++++++++++++++++++++++++++++++++++++
 llvm/test/CodeGen/ARM/stack_guard_remat.ll | 16 ++++++++++------
 llvm/test/LTO/ARM/ssp-static-reloc.ll      | 40 ----------------------------------------
 3 files changed, 51 insertions(+), 46 deletions(-)
```

https://github.com/llvm/llvm-project/pull/70014