staging: rtl8192u: Replaces symbolic permissions with octal permissions

Solves following checkpatch.pl issue:
WARNING: Symbolic permissions 'S_IRUGO' are not preferred. Consider
using octal permissions '0444'.
Signed-off-by: Camylla Goncalves Cantanheide <c.cantanheide@gmail.com>
Link: https://lore.kernel.org/r/20200317071959.556-1-c.cantanheide@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8192u/r8192U_core.c

@@ -613,13 +613,13 @@ static void rtl8192_proc_init_one(struct net_device *dev)
 	if (!dir)
 		return;
 
-	proc_create_single("stats-rx", S_IFREG | S_IRUGO, dir,
+	proc_create_single("stats-rx", S_IFREG | 0444, dir,
 			   proc_get_stats_rx);
-	proc_create_single("stats-tx", S_IFREG | S_IRUGO, dir,
+	proc_create_single("stats-tx", S_IFREG | 0444, dir,
 			   proc_get_stats_tx);
-	proc_create_single("stats-ap", S_IFREG | S_IRUGO, dir,
+	proc_create_single("stats-ap", S_IFREG | 0444, dir,
 			   proc_get_stats_ap);
-	proc_create_single("registers", S_IFREG | S_IRUGO, dir,
+	proc_create_single("registers", S_IFREG | 0444, dir,
 			   proc_get_registers);
 }