ima: fix ima_delete_rules() kernel-doc warning

Use correct kernel-doc syntax in the function description to
prevent a kernel-doc warning:

security/integrity/ima/ima_policy.c:1964: warning: expecting prototype for ima_delete_rules() called to cleanup invalid in(). Prototype was for ima_delete_rules() instead

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

security/integrity/ima/ima_policy.c

@@ -1955,7 +1955,8 @@ ssize_t ima_parse_add_rule(char *rule)
 }
 
 /**
- * ima_delete_rules() called to cleanup invalid in-flight policy.
+ * ima_delete_rules() - called to cleanup invalid in-flight policy.
+ *
  * We don't need locking as we operate on the temp list, which is
  * different from the active one.  There is also only one user of
  * ima_delete_rules() at a time.