Simplify usage of setFPAttrs.

In some cases using the return value of setFPAttrs simplifies the code.
In other cases it complicates the code with ugly casts, so stop doing
it. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@375409 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed