ALSA: info: Fix llseek return value when using callback

ALSA: info: Fix llseek return value when using callback

When using callback there was a flow of

	ret = -EINVAL
	if (callback) {
		offset = callback();
		goto out;
	}
	...
	offset = some other value in case of no callback;
	ret = offset;
out:
	return ret;

which causes the snd_info_entry_llseek() to return -EINVAL when there is
callback handler. Fix this by setting "ret" directly to callback return
value before jumping to "out".

Fixes: 7249eb18220b ("ALSA: info - Implement common llseek for binary mode")
Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220817124924.3974577-1-amadeuszx.slawinski@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>