x86: Remove use of .cfi_escape
x86: Remove use of .cfi_escape

The unwind info isn't 100% correct at all points during the epilogue,
and not annotating is just as incorrect as the annotation.  This works
better on systems that do not support DW_OP_call_frame_cfa.

bgarrels/libffi,joshtriplett/libffi,Distrotech/libffi,biosbits/libffi,nmav/libffi,biosbits/libffi,biosbits/libffi,rth7680/libffi,Pan7/libffi,Pan7/libffi,rth7680/libffi,Distrotech/libffi,bgarrels/libffi,bgarrels/libffi,s1341/libffi,rth7680/libffi,bgarrels/libffi,Pan7/libffi,joshtriplett/libffi,joshtriplett/libffi,s1341/libffi,nmav/libffi,plicease/libffi,Distrotech/libffi,s1341/libffi,s1341/libffi,biosbits/libffi,plicease/libffi,plicease/libffi,Distrotech/libffi,joshtriplett/libffi,plicease/libffi,nmav/libffi,nmav/libffi,Pan7/libffi,rth7680/libffi