package/duma: set HOST_CFLAGS

Set HOST_CFLAGS to avoid the following build failure raised since bump
to version 2.5.21 in commit af2cd694e3903131d6e2f00646adfa83a89a23e2:

/usr/bin/gcc -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -mlongcalls -mauto-litpools -O2 -g0   -c createconf.c -o createconf.o
gcc: error: unrecognized command-line option '-mlongcalls'
gcc: error: unrecognized command-line option '-mauto-litpools'

Fixes: af2cd694e3903131d6e2f00646adfa83a89a23e2
 - http://autobuild.buildroot.org/results/28be2acc6d58754c7431df81d0b63b30e6af8554

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit b8c70f67017ebe08459992ac575ae4989243c232)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/duma/duma.mk

@@ -20,6 +20,7 @@ define DUMA_BUILD_CMDS
 	$(TARGET_MAKE_ENV) $(MAKE1) $(TARGET_CONFIGURE_OPTS) \
 		OS=linux \
 		DUMA_OPTIONS="$(DUMA_OPTIONS)" \
+		HOST_CFLAGS="$(HOST_CFLAGS)" \
 		CPPFLAGS="$(TARGET_CXXFLAGS) -std=c++11" -C $(@D)
 endef