config: Fix -R option

The '-R' is short for '--leave-running', which is a boolean option and
does not require an argument.

From getopt(3) man page:

optstring is a string containing the legitimate option characters. If
such a character is followed by a colon, the option requires an
argument, ...
Signed-off-by: Radostin Stoyanov <rstoyanov1@gmail.com>

criu/config.c

@@ -436,7 +436,7 @@ int parse_options(int argc, char **argv, bool *usage_error,
 		{OPT_NAME, no_argument, SAVE_TO, true},\
 		{"no-" OPT_NAME, no_argument, SAVE_TO, false}
 
-	static const char short_opts[] = "dSsR:t:hD:o:v::x::Vr:jJ:lW:L:M:";
+	static const char short_opts[] = "dSsRt:hD:o:v::x::Vr:jJ:lW:L:M:";
 	static struct option long_opts[] = {
 		{ "tree",			required_argument,	0, 't'	},
 		{ "leave-stopped",		no_argument,		0, 's'	},