volume_id: Adopt to new config style.

Config instructions for util-linux/volume_id are moved into the
source files according to the new config feature.

No code change.

Signed-off-by: Sven-Göran Bergh <sgb@systemasis.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

util-linux/volume_id/squashfs.c

@@ -8,6 +8,18 @@
 
 //kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_SQUASHFS) += squashfs.o
 
+//config:
+//config:config FEATURE_VOLUMEID_SQUASHFS
+//config:	bool "SquashFS filesystem"
+//config:	default y
+//config:	depends on VOLUMEID && FEATURE_BLKID_TYPE
+//config:	help
+//config:	  Squashfs is a compressed read-only filesystem for Linux. Squashfs is
+//config:	  intended for general read-only filesystem use and in constrained block
+//config:	  device/memory systems (e.g. embedded systems) where low overhead is
+//config:	  needed.
+//config:
+
 #include "volume_id_internal.h"
 
 struct squashfs_superblock {