[ALSA] use convenient treble scale on WM8750

On Zaurus SL-C3200 (terrier/spitz) based on WM8750, treble scale is
inconveniently reverted (increase level = decrease treble), in opposite
to bass scale, which uses convenient scale.
Fix ALSA WM8750 mixer treble to use convenient treble scale (increase =
increase treble level)
From: Stanislav Brabec <utx@penguin.cz>

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
diff --git a/sound/soc/codecs/wm8750.c b/sound/soc/codecs/wm8750.c
index 28684ee..f8797de 100644
--- a/sound/soc/codecs/wm8750.c
+++ b/sound/soc/codecs/wm8750.c
@@ -189,7 +189,7 @@
 SOC_ENUM("Bass Filter", wm8750_enum[1]),
 SOC_SINGLE("Bass Volume", WM8750_BASS, 0, 15, 1),
 
-SOC_SINGLE("Treble Volume", WM8750_TREBLE, 0, 15, 0),
+SOC_SINGLE("Treble Volume", WM8750_TREBLE, 0, 15, 1),
 SOC_ENUM("Treble Cut-off", wm8750_enum[2]),
 
 SOC_SINGLE("3D Switch", WM8750_3D, 0, 1, 0),