fs/ext2: allow reserving zero block for root

The previous default, zero, just meant "use the default value of the
filesystem generator", which happened to be 5% (the traditional value
for all ext-creating tools we've ever seen).

So, change the new default accordingly to 5%.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

fs/ext2/Config.in

@@ -65,7 +65,12 @@ config BR2_TARGET_ROOTFS_EXT2_EXTRA_INODES
 
 config BR2_TARGET_ROOTFS_EXT2_RESBLKS
 	int "reserved blocks percentage"
-	default 0
+	default 5
+	help
+	  The number of blocks on the filesystem (as a percentage of the
+	  total number of blocksi), that are reserved for use by root.
+	  Traditionally, this has been 5%, and all ext-related tools still
+	  default to reserving 5% when creating a new ext filesystem.
 
 choice
 	prompt "Compression method"

fs/ext2/ext2.mk

@@ -12,9 +12,7 @@ EXT2_OPTS += -i $(BR2_TARGET_ROOTFS_EXT2_INODES)
 
 EXT2_OPTS += -I $(BR2_TARGET_ROOTFS_EXT2_EXTRA_INODES)
 
-ifneq ($(strip $(BR2_TARGET_ROOTFS_EXT2_RESBLKS)),0)
 EXT2_OPTS += -r $(BR2_TARGET_ROOTFS_EXT2_RESBLKS)
-endif
 
 # qstrip results in stripping consecutive spaces into a single one. So the
 # variable is not qstrip-ed to preserve the integrity of the string value.