UBUNTU: [Config] switch squashfs to single threaded decode

There is some issue with squashfs decoding when done in a multi-threaded
manner which leads to large memory consumption.  Either we have a leak
or more probabally we have pathalogical case leading to horrible internal
fragmentation.  For the moment turn it off while it can be investigated.

BugLink: http://bugs.launchpad.net/bugs/1636847Signed-off-by: Andy Whitcroft <apw@canonical.com>
Acked-by: Brad Figg <brad.figg@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

debian.master/config/config.common.ubuntu

@@ -7617,8 +7617,8 @@ CONFIG_SPU_FS=m
 CONFIG_SQUASHFS=y
 # CONFIG_SQUASHFS_4K_DEVBLK_SIZE is not set
 # CONFIG_SQUASHFS_DECOMP_MULTI is not set
-CONFIG_SQUASHFS_DECOMP_MULTI_PERCPU=y
-# CONFIG_SQUASHFS_DECOMP_SINGLE is not set
+# CONFIG_SQUASHFS_DECOMP_MULTI_PERCPU is not set
+CONFIG_SQUASHFS_DECOMP_SINGLE=y
 # CONFIG_SQUASHFS_EMBEDDED is not set
 # CONFIG_SQUASHFS_FILE_CACHE is not set
 CONFIG_SQUASHFS_FILE_DIRECT=y