[MIPS] Build libGLES for mips64, mips32r6

For now, use generic C code instead of assembler.

Change-Id: I604ecdcde2d5373f1f68ab97a63a80667b630846
diff --git a/opengl/libagl/matrix.h b/opengl/libagl/matrix.h
index 5bd717a..cafc119 100644
--- a/opengl/libagl/matrix.h
+++ b/opengl/libagl/matrix.h
@@ -74,7 +74,7 @@
         ); 
     return r;
 
-#elif defined(__mips__)
+#elif defined(__mips__) && !defined(__LP64__) && __mips_isa_rev < 6
 
     GLfixed res;
     int32_t t1,t2,t3;
@@ -160,7 +160,7 @@
         ); 
     return r;
     
-#elif defined(__mips__)
+#elif defined(__mips__)  && !defined(__LP64__) && __mips_isa_rev < 6
 
     GLfixed res;
     int32_t t1,t2;