Fix other arch build in detect.
When CORE is empty, use -march=loongson3a. Fix it.
@@ -847,7 +847,7 @@ CCOMMON_OPT += -mabi=32
BINARY_DEFINED = 1
endif
-ifeq ($(CORE), $(filter $(CORE),LOONGSON3R3 LOONGSON3R4))
+ifneq (, $(filter $(CORE),LOONGSON3R3 LOONGSON3R4))
CCOMMON_OPT += -march=loongson3a
FCOMMON_OPT += -march=loongson3a
endif
