[llvm-branch-commits] [Driver] Support -Wa, --fdpic for ARM FDPIC ABI (PR #82188)

[Fangrui Song via llvm-branch-commits]

https://github.com/MaskRay created https://github.com/llvm/llvm-project/pull/82188

`arm-linux-gnueabihf-gcc -c -fpic -mfdpic -Wa,--fdpic a.c` compiles
a.c with FDPIC codegen and assembles the assembly file with `--fdpic`.
This patch implements -Wa,--fdpic for the driver when using the
integrated assembler.