firmware loader: fix compile warning with PM_SLEEP set

This patch fixes the below compile warning:

drivers/base/firmware_class.c:1254:12: warning: 'cache_firmware' defined
but not used [-Wunused-function]
static int cache_firmware(const char *fw_name)
^
drivers/base/firmware_class.c:1281:12: warning: 'uncache_firmware'
defined but not used [-Wunused-function]
static int uncache_firmware(const char *fw_name)
^

Reported-by: Stephen Rothwell <[e-mail]>
Signed-off-by: Ming Lei <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/base/firmware_class.c

···
 }
 EXPORT_SYMBOL(request_firmware_nowait);
 
+#ifdef CONFIG_PM_SLEEP
+static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
+
 /**
  * cache_firmware - cache one firmware image in kernel memory space
  * @fw_name: the firmware image name
···
 
 	return -EINVAL;
 }
-
-#ifdef CONFIG_PM_SLEEP
-static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
 
 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
 {