Fix cc -ftrapping-math on macppc

Fix cc -ftrapping-math on macppc

Handle CALL_RM like CALL for 32-bit ELF.  If a function call has the
strictfp attribute, its opcode changes from CALL to CALL_RM.  If a
call uses the secure PLT, then it must getGlobalBaseReg() to set r30.

After I rebuilt xenocara/lib/pixman with this change, Xorg stopped
crashing on my macppc.  pixman uses cc -ftrapping-math which puts
strictfp on each function call.

https://github.com/llvm/llvm-project/pull/72758

ok jca@ tobhe@ deraadt@