Exclude rs_matrixNxN from being RS object type.

rs_matrix{2x2, 3x3, 4x4} (RS matrix type) is very different than RS
object type like rs_allocation. This commit teaches llvm-rs-cc to learn
it.

NOTE: Currenrly RS matrix type + RS object type = RS specific type.
diff --git a/RSSpec.mk b/RSSpec.mk
index 26f2eff..5a99b94 100644
--- a/RSSpec.mk
+++ b/RSSpec.mk
@@ -38,6 +38,12 @@
 	$(call generate-rs-spec-inc,rs-data-type-enums)
 endif
 
+ifneq ($(findstring RSMatrixTypeEnums.inc,$(RS_SPEC_TABLES)),)
+LOCAL_GENERATED_SOURCES += $(intermediates)/RSMatrixTypeEnums.inc
+$(intermediates)/RSMatrixTypeEnums.inc: $(RS_SPEC_GEN)
+	$(call generate-rs-spec-inc,rs-matrix-type-enums)
+endif
+
 ifneq ($(findstring RSObjectTypeEnums.inc,$(RS_SPEC_TABLES)),)
 LOCAL_GENERATED_SOURCES += $(intermediates)/RSObjectTypeEnums.inc
 $(intermediates)/RSObjectTypeEnums.inc: $(RS_SPEC_GEN)