domoticz: remove DOMOTICZ_CXXFLAGS

Since commit 6be346cec40dda8ab762e11471fa6ff951fdbfa0,
DOMOTICZ_CXXFLAGS is not set anymore so remove it

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

package/domoticz/domoticz.mk

@@ -27,8 +27,7 @@ DOMOTICZ_CONF_OPTS += -DUSE_STATIC_BOOST=OFF
 DOMOTICZ_CONF_OPTS += \
 	-DUSE_BUILTIN_LUA=OFF \
 	-DUSE_BUILTIN_SQLITE=OFF \
-	-DUSE_BUILTIN_MQTT=OFF \
-	-DCMAKE_CXX_FLAGS="$(TARGET_CXXFLAGS) $(DOMOTICZ_CXXFLAGS)"
+	-DUSE_BUILTIN_MQTT=OFF
 
 ifeq ($(BR2_PACKAGE_LIBUSB),y)
 DOMOTICZ_DEPENDENCIES += libusb