Silence a silly sign compare warning from GCC.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180673 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/DeclSpec.cpp b/lib/Sema/DeclSpec.cpp
index 998e2c0..124f50c 100644
--- a/lib/Sema/DeclSpec.cpp
+++ b/lib/Sema/DeclSpec.cpp
@@ -847,7 +847,7 @@
        TypeSpecSign != TSS_unspecified ||
        TypeAltiVecVector || TypeAltiVecPixel || TypeAltiVecBool ||
        TypeQualifiers)) {
-    const int NumLocs = 8;
+    const unsigned NumLocs = 8;
     SourceLocation ExtraLocs[NumLocs] = {
       TSWLoc, TSCLoc, TSSLoc, AltiVecLoc,
       TQ_constLoc, TQ_restrictLoc, TQ_volatileLoc, TQ_atomicLoc