These are added mainly for the benefit of clang, but this also means that they
are now allowed in .fpu directives and we emit the correct .fpu directive when
single-precision-only is used.
Differential Revision: http://reviews.llvm.org/D10238
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239151 91177308-0d34-0410-b5e6-96231b3b80d8