fs: pass EXTRA_ENV to post-fakeroot script

Like we do for post-build and post-image scripts, pass EXTRA_ENV to
post-fakeroot script.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

fs/common.mk

@@ -95,7 +95,7 @@ endif
 	echo "$$(HOST_DIR)/bin/makedevs -d $$(FULL_DEVICE_TABLE) $$(TARGET_DIR)" >> $$(FAKEROOT_SCRIPT)
 	$$(foreach s,$$(call qstrip,$$(BR2_ROOTFS_POST_FAKEROOT_SCRIPT)),\
 		echo "echo '$$(TERM_BOLD)>>>   Executing fakeroot script $$(s)$$(TERM_RESET)'" >> $$(FAKEROOT_SCRIPT); \
-		echo $$(s) $$(TARGET_DIR) $$(BR2_ROOTFS_POST_SCRIPT_ARGS) >> $$(FAKEROOT_SCRIPT)$$(sep))
+		echo $$(EXTRA_ENV) $$(s) $$(TARGET_DIR) $$(BR2_ROOTFS_POST_SCRIPT_ARGS) >> $$(FAKEROOT_SCRIPT)$$(sep))
 	$$(foreach hook,$$(ROOTFS_PRE_CMD_HOOKS),\
 		$$(call PRINTF,$$($$(hook))) >> $$(FAKEROOT_SCRIPT)$$(sep))
 ifeq ($$(BR2_REPRODUCIBLE),y)