Input: lm8323 - fix checking PWM interrupt status

INT_PWM1 is already a bitmask, not the bit number, so shifting by INT_PWM1 is
incorrect.

Signed-off-by: Nickolai Zeldovich <nickolai@csail.mit.edu>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>