fs/cachefiles: simplify one-level sysctl registration for cachefiles_sysctls

There is no need to declare an extra tables to just create directory,
this can be easily be done with a prefix path with register_sysctl().

Simplify this registration.
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

fs/cachefiles/error_inject.c

@@ -22,18 +22,9 @@ static struct ctl_table cachefiles_sysctls[] = {
 	{}
 };
 
-static struct ctl_table cachefiles_sysctls_root[] = {
-	{
-		.procname	= "cachefiles",
-		.mode		= 0555,
-		.child		= cachefiles_sysctls,
-	},
-	{}
-};
-
 int __init cachefiles_register_error_injection(void)
 {
-	cachefiles_sysctl = register_sysctl_table(cachefiles_sysctls_root);
+	cachefiles_sysctl = register_sysctl("cachefiles", cachefiles_sysctls);
 	if (!cachefiles_sysctl)
 		return -ENOMEM;
 	return 0;