Fix tests to use fadd, fsub, and fmul, instead of add, sub, and mul,

Fix tests to use fadd, fsub, and fmul, instead of add, sub, and mul,
when the type is floating-point.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102969 91177308-0d34-0410-b5e6-96231b3b80d8