Add a new pwm app (motor control) using the new API.
Following the recent pwm RFC, all existing APIs will
be deprecated. Two new APIs will be added. The changes
for the new APIs and the required driver function have
been posted.
To demonstrate the usage of the new PWM APIs, this app
to drive a servo motor is added. It will use the new
API pwm_pin_set_usec().
This app will be located in a new sub directory.
Jira: ZEP-745 ZEP-1029
Origin: Original
Change-Id: I65857848e64d0478c4e12d1317b2089cdd1ecf5c
Signed-off-by: Baohong Liu <baohong.liu@intel.com>