ath10k: add modpram 'skip_otp' to ignore empty otp error during BMI

This patch would help bring up wifi interface with default board
data in case of failures in otp download. It is useful for initial
calibration.

Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>