stepper: optimize latency in starting motor

stepper: optimize latency in starting motor

Avoid reading the motor status before sending start motor
command. This saves one read transaction while starting motor.

Bug 1623721

Change-Id: Ibee8025fafa2e19419c1f635f91d508400b829c0
Signed-off-by: Vishruth <vishruthj@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1554456
GVS: Gerrit_Virtual_Submit
Reviewed-by: Bibek Basu <bbasu@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>