x86: Force FFI_TYPE_LONGDOUBLE different from FFI_TYPE_DOUBLE
x86: Force FFI_TYPE_LONGDOUBLE different from FFI_TYPE_DOUBLE

There are few abis that set double = long double.  Eliminate the
conditional compilation and let this code simply be unused there.

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