generic: revert to OpenWrt CC partition sizes on x86 and similar images for now

This will allow upgrading using the broken sysupgrade scripts in OpenWrt
CC without losing the configuration.

Fixes #1010

targets/generic

@@ -11,6 +11,9 @@ config 'CONFIG_PACKAGE_ATH_DEBUG=y'
 config 'CONFIG_TARGET_MULTI_PROFILE=y'
 config 'CONFIG_TARGET_PER_DEVICE_ROOTFS=y'
 
+config 'CONFIG_TARGET_KERNEL_PARTSIZE=4'
+config 'CONFIG_TARGET_ROOTFS_PARTSIZE=48'
+
 if [ "$GLUON_DEBUG" ]
 then
 	config 'CONFIG_DEBUG=y'