drv_pwm_output: include board config header
drv_pwm_output: include board config header

- board config can define PX4_PWM_ALTERNATE_RANGES which needs to be known
by the compiler prior to processing this file

Signed-off-by: Roman <019237760eff64d50a7eec108f84e3d8840aac17@gmail.com>

PX4/Firmware,mcgill-robotics/Firmware,PX4/Firmware,Aerotenna/Firmware,dagar/Firmware,mje-nz/PX4-Firmware,mcgill-robotics/Firmware,Aerotenna/Firmware,Aerotenna/Firmware,dagar/Firmware,krbeverx/Firmware,dagar/Firmware,PX4/Firmware,PX4/Firmware,PX4/Firmware,mcgill-robotics/Firmware,dagar/Firmware,Aerotenna/Firmware,Aerotenna/Firmware,mcgill-robotics/Firmware,Aerotenna/Firmware,krbeverx/Firmware,acfloria/Firmware,dagar/Firmware,acfloria/Firmware,krbeverx/Firmware,mje-nz/PX4-Firmware,mje-nz/PX4-Firmware,acfloria/Firmware,mje-nz/PX4-Firmware,Aerotenna/Firmware,mcgill-robotics/Firmware,dagar/Firmware,mje-nz/PX4-Firmware,dagar/Firmware,mje-nz/PX4-Firmware,krbeverx/Firmware,acfloria/Firmware,krbeverx/Firmware,mcgill-robotics/Firmware,krbeverx/Firmware,PX4/Firmware,mcgill-robotics/Firmware,acfloria/Firmware,mje-nz/PX4-Firmware,acfloria/Firmware,krbeverx/Firmware,acfloria/Firmware,PX4/Firmware