[coro] Tweak comments about CoroAwaitSuspendInst

to reflect that there are three variants.

Author: zmodem

llvm/lib/Transforms/Coroutines/CoroInstr.h

@@ -78,10 +78,10 @@ class LLVM_LIBRARY_VISIBILITY CoroAllocInst : public IntrinsicInst {
   }
 };
 
-/// This represents the llvm.coro.await.suspend instruction.
+/// This represents the llvm.coro.await.suspend.{void,bool,handle} instructions.
 // FIXME: add callback metadata
 // FIXME: make a proper IntrinisicInst. Currently this is not possible,
-// because llvm.coro.await.suspend can be invoked.
+// because llvm.coro.await.suspend.* can be invoked.
 class LLVM_LIBRARY_VISIBILITY CoroAwaitSuspendInst : public CallBase {
   enum { AwaiterArg, FrameArg, WrapperArg };