config/files-reg: Add opt to skip file r/w/x check on restore

A file's r/w/x changing between checkpoint and restore does
not necessarily imply that something is wrong. For example,
if a process opens a file having perms rw- for reading and
we change the perms to r--, the process can be restored and
will function as expected.

Therefore, this patch adds an option

--skip-file-rwx-check

to disable this check on restore. File validation is unaffected
and should still function as expected with respect to the content
of files.

Signed-off-by: Younes Manton <ymanton@ca.ibm.com>

images/rpc.proto

@@ -138,6 +138,7 @@ message criu_opts {
 	optional string			lsm_mount_context	= 63;
 	optional criu_network_lock_method	network_lock		= 64 [default = IPTABLES];
 	optional bool			mntns_compat_mode	= 65;
+	optional bool			skip_file_rwx_check	= 66;
 /*	optional bool			check_mounts		= 128;	*/
 }