[llvm] [NFC][RISCV] Move Zvfbf* relative stuffs to RISCVInstrInfoZvfbf.td (PR #159619)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-nvptx64-nvidia-ubuntu` running on `as-builder-7` while building `llvm` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/160/builds/25223

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

```
Step 5 (build-unified-tree) failure: build (failure)
...
10.349 [1/8/81] Building CXX object utils/TableGen/Common/CMakeFiles/obj.LLVMTableGenCommon.dir/CodeGenSchedule.cpp.o
11.238 [1/7/82] Building CXX object utils/TableGen/CMakeFiles/llvm-tblgen.dir/RegisterInfoEmitter.cpp.o
11.909 [1/6/83] Building CXX object utils/TableGen/CMakeFiles/llvm-tblgen.dir/AsmMatcherEmitter.cpp.o
12.792 [1/5/84] Building CXX object utils/TableGen/Common/CMakeFiles/obj.LLVMTableGenCommon.dir/GlobalISel/GlobalISelMatchTable.cpp.o
13.479 [1/4/85] Building CXX object utils/TableGen/CMakeFiles/llvm-tblgen.dir/GlobalISelCombinerEmitter.cpp.o
13.999 [1/3/86] Building CXX object utils/TableGen/Common/CMakeFiles/obj.LLVMTableGenCommon.dir/CodeGenDAGPatterns.cpp.o
14.762 [1/2/87] Building CXX object utils/TableGen/Common/CMakeFiles/obj.LLVMTableGenCommon.dir/CodeGenRegisters.cpp.o
16.192 [1/1/88] Building CXX object utils/TableGen/CMakeFiles/llvm-tblgen.dir/GlobalISelEmitter.cpp.o
16.554 [0/1/89] Linking CXX executable bin/llvm-tblgen
33.430 [2266/2/558] Building RISCVTargetParserDef.inc...
FAILED: include/llvm/TargetParser/RISCVTargetParserDef.inc /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/build/include/llvm/TargetParser/RISCVTargetParserDef.inc 
cd /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/build/include/llvm/TargetParser && /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/build/NATIVE/bin/llvm-min-tblgen -gen-riscv-target-def -I/home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/llvm-project/llvm/include/llvm/TargetParser -I/home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/llvm-project/llvm/lib/Target/RISCV -I/home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/build/include -I/home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/llvm-project/llvm/include /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/llvm-project/llvm/lib/Target/RISCV/RISCV.td --write-if-changed -o RISCVTargetParserDef.inc -d RISCVTargetParserDef.inc.d && /usr/bin/cmake -E cmake_transform_depfile Ninja gccdepfile /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/llvm-project/llvm /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/llvm-project/llvm/include/llvm/TargetParser /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/build /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/build/include/llvm/TargetParser /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/build/include/llvm/TargetParser/RISCVTargetParserDef.inc.d /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/build/CMakeFiles/d/21e299b30b15bec3f3c2b7b44fde3b75a25eae0545d97c03715c6a6487327779.d
Included from /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/llvm-project/llvm/lib/Target/RISCV/RISCV.td:36:
Included from /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/llvm-project/llvm/lib/Target/RISCV/RISCVInstrInfo.td:2344:
Included from /home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/llvm-project/llvm/lib/Target/RISCV/RISCVInstrInfoV.td:1842:
/home/buildbot/worker/as-builder-7/llvm-nvptx64-nvidia-ubuntu/llvm-project/llvm/lib/Target/RISCV/RISCVInstrInfoZvfbf.td:39:19: error: Variable not defined: 'HasStdExtZvfbfmin'
let Predicates = [HasStdExtZvfbfmin] in {
                  ^
ninja: build stopped: subcommand failed.

```

</details>

https://github.com/llvm/llvm-project/pull/159619