Revert "ALSA: sb8: add a check for request_region"

stable inclusion
from linux-4.19.192
commit 14b3bb3da626129da01f6db48e13b9220b7913ed

--------------------------------

commit 94f88309 upstream.

This reverts commit dcd0feac.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be incorrect for the reasons
below, so it must be reverted.  It will be fixed up "correctly" in a
later kernel change.

The original commit message for this change was incorrect as the code
path can never result in a NULL dereference, alluding to the fact that
whatever tool was used to "find this" is broken.  It's just an optional
resource reservation, so removing this check is fine.

Cc: Kangjie Lu <kjlu@umn.edu>
Acked-by: NTakashi Iwai <tiwai@suse.de>
Fixes: dcd0feac ("ALSA: sb8: add a check for request_region")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210503115736.2104747-35-gregkh@linuxfoundation.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

sound/isa/sb/sb8.c

@@ -111,10 +111,6 @@ static int snd_sb8_probe(struct device *pdev, unsigned int dev)
 
 	/* block the 0x388 port to avoid PnP conflicts */
 	acard->fm_res = request_region(0x388, 4, "SoundBlaster FM");
-	if (!acard->fm_res) {
-		err = -EBUSY;
-		goto _err;
-	}
 
 	if (port[dev] != SNDRV_AUTO_PORT) {
 		if ((err = snd_sbdsp_create(card, port[dev], irq[dev],