Fix arm_neon.h and arm_fp16.h generation for compiling with std=c89


Summary:
The inline attribute is not valid for C standard 89. Replace the argument in the generation of header files with __inline, as well adding tests for both header files.

Reviewers: pbarrio, SjoerdMeijer, javed.absar, t.p.northover

Subscribers: t.p.northover, kristof.beyls, chrib, cfe-commits

Differential Revision: https://reviews.llvm.org/D51683

test/Headers/arm-fp16-header.c
test/Headers/arm-neon-header.c
utils/TableGen/NeonEmitter.cpp

llvm-svn: 341475
diff --git a/clang/utils/TableGen/NeonEmitter.cpp b/clang/utils/TableGen/NeonEmitter.cpp
index eca03a5..c7ff004 100644
--- a/clang/utils/TableGen/NeonEmitter.cpp
+++ b/clang/utils/TableGen/NeonEmitter.cpp
@@ -2409,7 +2409,7 @@
     OS << "#endif\n";
   OS << "\n";
 
-  OS << "#define __ai static inline __attribute__((__always_inline__, "
+  OS << "#define __ai static __inline __attribute__((__always_inline__, "
         "__nodebug__))\n\n";
 
   SmallVector<Intrinsic *, 128> Defs;
@@ -2518,7 +2518,7 @@
 
   OS << "typedef __fp16 float16_t;\n";
 
-  OS << "#define __ai static inline __attribute__((__always_inline__, "
+  OS << "#define __ai static __inline __attribute__((__always_inline__, "
         "__nodebug__))\n\n";
 
   SmallVector<Intrinsic *, 128> Defs;