sgi-xp: make some symbols static in xpc_main.c

Fix the following sparse warning:

drivers/misc/sgi-xp/xpc_main.c:62:22: warning: symbol 'xpc_dbg_name' was
not declared. Should it be static?
drivers/misc/sgi-xp/xpc_main.c:66:15: warning: symbol
'xpc_part_dbg_subname' was not declared. Should it be static?
drivers/misc/sgi-xp/xpc_main.c:71:15: warning: symbol
'xpc_chan_dbg_subname' was not declared. Should it be static?
drivers/misc/sgi-xp/xpc_main.c:1221:1: warning: symbol 'xpc_init' was
not declared. Should it be static?
drivers/misc/sgi-xp/xpc_main.c:1323:1: warning: symbol 'xpc_exit' was
not declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200410063618.27143-2-yanaijie@huawei.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/sgi-xp/xpc_main.c

@@ -59,16 +59,16 @@
 
 /* define two XPC debug device structures to be used with dev_dbg() et al */
 
-struct device_driver xpc_dbg_name = {
+static struct device_driver xpc_dbg_name = {
 	.name = "xpc"
 };
 
-struct device xpc_part_dbg_subname = {
+static struct device xpc_part_dbg_subname = {
 	.init_name = "",	/* set to "part" at xpc_init() time */
 	.driver = &xpc_dbg_name
 };
 
-struct device xpc_chan_dbg_subname = {
+static struct device xpc_chan_dbg_subname = {
 	.init_name = "",	/* set to "chan" at xpc_init() time */
 	.driver = &xpc_dbg_name
 };
@@ -1217,7 +1217,7 @@ xpc_system_die(struct notifier_block *nb, unsigned long event, void *_die_args)
 	return NOTIFY_DONE;
 }
 
-int __init
+static int __init
 xpc_init(void)
 {
 	int ret;
@@ -1319,7 +1319,7 @@ xpc_init(void)
 
 module_init(xpc_init);
 
-void __exit
+static void __exit
 xpc_exit(void)
 {
 	xpc_do_exit(xpUnloading);