Change Neon polynomial types to be signed to match GCC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119405 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/NeonEmitter.cpp b/utils/TableGen/NeonEmitter.cpp
index 1c0edd1..333ca2f 100644
--- a/utils/TableGen/NeonEmitter.cpp
+++ b/utils/TableGen/NeonEmitter.cpp
@@ -833,8 +833,8 @@
 
   // Emit NEON-specific scalar typedefs.
   OS << "typedef float float32_t;\n";
-  OS << "typedef uint8_t poly8_t;\n";
-  OS << "typedef uint16_t poly16_t;\n";
+  OS << "typedef int8_t poly8_t;\n";
+  OS << "typedef int16_t poly16_t;\n";
   OS << "typedef uint16_t float16_t;\n";
 
   // Emit Neon vector typedefs.