[ELF] Make -V an alias for -v

In GNU ld,

* --version skips linker input processing.
* -v and -V keep processing if there is any input file. -V has more
  information we don't support.

We currently make -V an alias for --version which skips input processing.
On many `*-freebsd` and `powerpc-*` targets, `gcc -v` passes `-V` to ld
and expects to process input. Make -V an alias for -v to provide
compatibility.

Fix https://github.com/llvm/llvm-project/issues/57859