Small fix for gcc8.

The linker will segfault for me when mcpu is not specified.

Makefile

@@ -196,8 +196,8 @@ else ifneq (,$(findstring odroid,$(platform)))
 	else ifneq (,$(findstring ODROID-XU3,$(BOARD)))
 		# ODROID-XU3 & -XU3 Lite
 		ifeq "$(shell expr `gcc -dumpversion` \>= 4.9)" "1"
-			CFLAGS += -march=armv7ve -mtune=cortex-a15.cortex-a7 -mfpu=neon-vfpv4 -mvectorize-with-neon-quad
-			CXXFLAGS += -march=armv7ve -mtune=cortex-a15.cortex-a7 -mfpu=neon-vfpv4 -mvectorize-with-neon-quad
+			CFLAGS += -march=armv7ve -mcpu=cortex-a15.cortex-a7 -mtune=cortex-a15.cortex-a7 -mfpu=neon-vfpv4 -mvectorize-with-neon-quad
+			CXXFLAGS += -march=armv7ve -mcpu=cortex-a15.cortex-a7 -mtune=cortex-a15.cortex-a7 -mfpu=neon-vfpv4 -mvectorize-with-neon-quad
 		else
 			CFLAGS += -mcpu=cortex-a9 -mfpu=neon
 			CXXFLAGS += -mcpu=cortex-a9 -mfpu=neon
@@ -205,8 +205,8 @@ else ifneq (,$(findstring odroid,$(platform)))
 	else ifneq (,$(findstring ODROID-XU4,$(BOARD)))
 		# ODROID-XU4 on newer kernels now identify as ODROID-XU4
 		ifeq "$(shell expr `gcc -dumpversion` \>= 4.9)" "1"
-			CFLAGS += -march=armv7ve -mtune=cortex-a15.cortex-a7 -mfpu=neon-vfpv4 -mvectorize-with-neon-quad
-			CXXFLAGS += -march=armv7ve -mtune=cortex-a15.cortex-a7 -mfpu=neon-vfpv4 -mvectorize-with-neon-quad
+			CFLAGS += -march=armv7ve -mcpu=cortex-a15.cortex-a7 -mtune=cortex-a15.cortex-a7 -mfpu=neon-vfpv4 -mvectorize-with-neon-quad
+			CXXFLAGS += -march=armv7ve -mcpu=cortex-a15.cortex-a7 -mtune=cortex-a15.cortex-a7 -mfpu=neon-vfpv4 -mvectorize-with-neon-quad
 		else
 			CFLAGS += -mcpu=cortex-a9 -mfpu=neon
 			CXXFLAGS += -mcpu=cortex-a9 -mfpu=neon