[source] include: image.mk: make ext4 reserved blocks percentage optional

[LEDE Commits]

jow pushed a commit to source.git, branch master:
https://git.lede-project.org/244955de166b14282e4d2b7ddcdcb72a653b5434

commit 244955de166b14282e4d2b7ddcdcb72a653b5434
Author: Jo-Philipp Wich <jo at mein.io>
AuthorDate: Sun Oct 16 01:59:42 2016 +0200

    include: image.mk: make ext4 reserved blocks percentage optional
    
    Allow CONFIG_TARGET_EXT4_RESERVED_PCT to be empty as make_ext4fs is usually
    able to figure out a suitable default.
    
    Signed-off-by: Jo-Philipp Wich <jo at mein.io>
    Reviewed-by: Michael Heimpold <mhei at heimpold.de>
---
 include/image.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/image.mk b/include/image.mk
index 8b7d91d..59dd66f 100644
--- a/include/image.mk
+++ b/include/image.mk
@@ -245,7 +245,7 @@ define Image/mkfs/ext4
 	$(STAGING_DIR_HOST)/bin/make_ext4fs \
 		-l $(E2SIZE) -b $(CONFIG_TARGET_EXT4_BLOCKSIZE) \
 		-i $(CONFIG_TARGET_EXT4_MAXINODE) \
-		-m $(CONFIG_TARGET_EXT4_RESERVED_PCT) \
+		$(if $(CONFIG_TARGET_EXT4_RESERVED_PCT),-m $(CONFIG_TARGET_EXT4_RESERVED_PCT)) \
 		$(if $(CONFIG_TARGET_EXT4_JOURNAL),,-J) \
 		$(if $(SOURCE_DATE_EPOCH),-T $(SOURCE_DATE_EPOCH)) \
 		$@ $(call mkfs_target_dir,$(1))/