package/elfutils: drop ELFUTILS_{C,CPP}FLAGS

ELFUTILS_CFLAGS and ELFUTILS_CPPFLAGS are empty since commit
7593aea519dee34cb25715296c1b03f471123ee2 so drop them to avoid setting
incorrect flags

Fixes: 7593aea519dee34cb25715296c1b03f471123ee2

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/elfutils/elfutils.mk

@@ -29,10 +29,6 @@ HOST_ELFUTILS_CONF_OPTS = \
 	--without-zstd \
 	--disable-progs
 
-ELFUTILS_CONF_ENV += \
-	CFLAGS="$(ELFUTILS_CFLAGS)" \
-	CPPFLAGS="$(ELFUTILS_CPPFLAGS)"
-
 ELFUTILS_LDFLAGS = $(TARGET_LDFLAGS) \
 	$(TARGET_NLS_LIBS)