squashfs: bump version

target/squashfs/squashfsroot.mk

@@ -3,7 +3,7 @@
 # mksquashfs to build to target squashfs filesystems
 #
 #############################################################
-SQUASHFS_VERSION:=3.3
+SQUASHFS_VERSION:=3.4
 SQUASHFS_DIR:=$(BUILD_DIR)/squashfs$(SQUASHFS_VERSION)
 SQUASHFS_SOURCE:=squashfs$(SQUASHFS_VERSION).tar.gz
 SQUASHFS_SITE:=http://$(BR2_SOURCEFORGE_MIRROR).dl.sourceforge.net/sourceforge/squashfs