drm/amd/powerplay: implement pwm1_enable hwmon interface for SMU11 (v2)

1, set get_pwm1_enable and set_pwm1_enable functions to call
smu_get_fan_control_mode and smu_set_fan_control_mode for SMU11
2, implement set_fan_control_mode function

v2: add return value in set_fan_control_mode function

Signed-off-by: Chengming Gui <Jack.Gui@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>