Fix an enumeral mismatch warning.

[hokein]

Summary

The "-Werror=enum-compare" shows that the statement is using two different enums:

enumeral mismatch in conditional expression: 'llvm::X86ISD::NodeType' vs 'llvm::ISD::NodeType'

A follow-up fix on D21235.

[klimek]

LG. Fix the change description when submitting, though - this is not about an enum comparison, right?

[hokein]

In D21278#455850, @klimek wrote:

LG. Fix the change description when submitting, though - this is not about an enum comparison, right?

Done. This is enumeral mismatch indeed.

lib/Target/X86/X86ISelLowering.cpp

#endif
     unsigned SSECC = translateX86FSETCC(SetCCOpcode, Op0, Op1);
     if (SSECC == 8) {
       // LLVM predicate is SETUEQ or SETONE.
       unsigned CC0, CC1;
       unsigned CombineOpc;
       if (SetCCOpcode == ISD::SETUEQ) {
         CC0 = 3; // UNORD
         CC1 = 0; // EQ
-        CombineOpc = Opc == X86ISD::CMPP ? X86ISD::FOR : ISD::OR;
+        CombineOpc = Opc == X86ISD::CMPP ? static_cast<unsigned>(X86ISD::FOR) :
+                                           static_cast<unsigned>(ISD::OR);
       } else {
         assert(SetCCOpcode == ISD::SETONE);
         CC0 = 7; // ORD
         CC1 = 4; // NEQ
-        CombineOpc = Opc == X86ISD::CMPP ? X86ISD::FAND : ISD::AND;
+        CombineOpc = Opc == X86ISD::CMPP ? static_cast<unsigned>(X86ISD::FAND) :
+                                           static_cast<unsigned>(ISD::AND);
       }
 
       SDValue Cmp0 = DAG.getNode(Opc, dl, VT, Op0, Op1,
                                  DAG.getConstant(CC0, dl, MVT::i8));
       SDValue Cmp1 = DAG.getNode(Opc, dl, VT, Op0, Op1,
                                  DAG.getConstant(CC1, dl, MVT::i8));
       Cmp = DAG.getNode(CombineOpc, dl, VT, Cmp0, Cmp1);
     } else {