Another attempt to skip the fast-math linker test on powerpc. The test
has to be skipped because there is no crtfastmath.o on powerpc.
Change recommended by Amy Kwan <amyk>.
See https://reviews.llvm.org/D138675
! Check that -ffast-math causes us to link to crtfastmath.o
! UNSUPPORTED: system-windows
-! UNSUPPORTED: target={{p(ower)?pc.*}}
+! UNSUPPORTED: powerpc-registered-target
! RUN: %flang -ffast-math -### %s -o %t 2>&1 \
! RUN: | FileCheck --check-prefix=CHECK-CRT %s
! CHECK-CRT: {{crtbegin.?\.o}}