[SelectionDAGBuilder] Use CallBase::isInlineAsm in a couple places. NFC

These lines were just changed from using CallBase::getCalledValue
to getCallledOperand. Go aheand change them to isInlineAsm.

Author: topperc

llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

@@ -346,7 +346,7 @@ static void diagnosePossiblyInvalidConstraint(LLVMContext &Ctx, const Value *V,
 
   const char *AsmError = ", possible invalid constraint for vector type";
   if (const CallInst *CI = dyn_cast<CallInst>(I))
-    if (isa<InlineAsm>(CI->getCalledOperand()))
+    if (CI->isInlineAsm())
       return Ctx.emitError(I, ErrMsg + AsmError);
 
   return Ctx.emitError(I, ErrMsg);
@@ -2856,8 +2856,7 @@ void SelectionDAGBuilder::visitCallBr(const CallBrInst &I) {
              {LLVMContext::OB_deopt, LLVMContext::OB_funclet}) &&
          "Cannot lower callbrs with arbitrary operand bundles yet!");
 
-  assert(isa<InlineAsm>(I.getCalledOperand()) &&
-         "Only know how to handle inlineasm callbr");
+  assert(I.isInlineAsm() && "Only know how to handle inlineasm callbr");
   visitInlineAsm(I);
   CopyToExportRegsIfNeeded(&I);