Add support for ellcc, Credit to Richard Pennington.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@79332 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/endianness.h b/lib/endianness.h
index a123acd..28b0ace 100644
--- a/lib/endianness.h
+++ b/lib/endianness.h
@@ -52,7 +52,7 @@
 /* .. */
 
 /* Mac OSX has __BIG_ENDIAN__ or __LITTLE_ENDIAN__ automatically set by the compiler (at least with GCC) */
-#if defined(__APPLE__) && defined(__MACH__)
+#if defined(__APPLE__) && defined(__MACH__) || defined(__ellcc__ )
 
 #ifdef __BIG_ENDIAN__
 #if __BIG_ENDIAN__