Docs: remove extra {} around result types.

It makes the types look like they're single-element structures. And
when we have instructions that *do* result in a struct, that can get
confusing rather quickly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210905 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed