message: Added print of LLVM patch version
diff: #define __ispc__xstr(s) __ispc__str(s)
  #define __ispc__str(s) #s
  -#define ISPC_LLVM_VERSION_STRING __ispc__xstr(LLVM_VERSION_MAJOR) "." __ispc__xstr(LLVM_VERSION_MINOR)
  +#define ISPC_LLVM_VERSION_STRING __ispc__xstr(LLVM_VERSION_MAJOR) "." __ispc__xstr(LLVM_VERSION_MINOR) "." __ispc__xstr(LLVM_VERSION_PATCH)
  #if ISPC_LLVM_VERSION < OLDEST_SUPPORTED_LLVM || ISPC_LLVM_VERSION > LATEST_SUPPORTED_LLVM
  #error "Unhandled LLVM version"
  