[AIX] supporting -X options for llvm-ranlib in AIX OS

Summary:

llvm-ar is symlinked as llvm-ranlib and will act as ranlib when invoked in that mode. llvm-ar since [[ https://github.ibm.com/compiler/llvm-project/commit/4f2cfbe5314b064625b2c87bde6ce5c8d04004c5 | compiler/llvm-project@4f2cfbe ]] supports the -X options, but doesn't seem to accept them when running as llvm-ranlib.

In AIX OS , according to https://www.ibm.com/docs/en/aix/7.2?topic=r-ranlib-command

-X mode 	Specifies the type of object file ranlib should examine. The mode must be one of the following:

32
    Processes only 32-bit object files
64
    Processes only 64-bit object files
32_64, any
    Processes both 32-bit and 64-bit object files

The default is to process 32-bit object files (ignore 64-bit objects). The mode can also be set with the OBJECT_MODE environment variable. For example, OBJECT_MODE=64 causes ranlib to process any 64-bit objects and ignore 32-bit objects. The -X flag overrides the OBJECT_MODE variable.

Reviewers: James Henderson, MaskRay, Stephen Peckham
Differential Revision: https://reviews.llvm.org/D142660