[PATCH] Move VFP4 predicate inside UseFusedMAC

[Tim Northover]

> Basically, UseFusedMAC isn't being checked by the assembler and it
> would give incorrect results even if it was.

Just a quick example:

echo vfma.f32 d0, d1, d2 | llvm-mc -triple=armv7 -mcpu=cortex-a8

Tim.