ALSA: vx: hard dependency on the standard fw loader

Yet again like previous two commits, drop the old hwdep user-space
firmware code from vx driver (snd-vxpocket and snd-vx222).

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/drivers/Kconfig b/sound/drivers/Kconfig
index 5e43841..7d02c32 100644
--- a/sound/drivers/Kconfig
+++ b/sound/drivers/Kconfig
@@ -14,6 +14,7 @@
 
 config SND_VX_LIB
 	tristate
+	select FW_LOADER
 	select SND_HWDEP
 	select SND_PCM