techpack: audio: 4.0: tas2562: Fix Amp output level control

TAS2562 datasheet specifies that amp_level value is represented
by bits[5:1] with maximal value 0x1c (values 0x1d-0x1f are
marked as reserved. Fix maximum and shift value of associated sound
control accordingly (max value 0x1c and shift 1).

Signed-off-by: Ivan Vecera <ivan@cera.cz>
Change-Id: I77be6a744ba4de8a51c91eba5602e4fdfb88b3ac
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>