parser: add parser support for io_uring mediation

io_uring rules have the following format:

io_uring [<access_mode>] [<label>],
access_mode := 'sqpoll'|'override_creds'
label := 'label' '=' <target label>

Signed-off-by: Georgia Garcia <georgia.garcia@canonical.com>

parser/parser_misc.c

@@ -124,6 +124,9 @@ static struct keyword_table keyword_table[] = {
 	{"mqueue",		TOK_MQUEUE},
 	{"delete",		TOK_DELETE},
 	{"open",		TOK_OPEN},
+	{"io_uring",		TOK_IO_URING},
+	{"override_creds",	TOK_OVERRIDE_CREDS},
+	{"sqpoll",		TOK_SQPOLL},
 
 	/* terminate */
 	{NULL, 0}