Remove arm assembler not referenced from any makefile.

I also suspect that libc/arch-arm/bionic/memcmp.S is supposed to like in the
generic directory these days, but this change just removes dead code.

Change-Id: I9072488df6e9b7261d79b6014914a0e937cb387b
Merge "Remove arm assembler not referenced from any makefile."
Move the generic arm memcmp.S into the generic directory.

Change-Id: I48e4d14a0dcddbb246edbac6d0329619574ab44d
Merge "Move the generic arm memcmp.S into the generic directory."