drm/i915/hwmon: Enable PL1 power limit

Previous documentation suggested that PL1 power limit is always
enabled. However we now find this not to be the case on some
platforms (such as ATSM). Therefore enable PL1 power limit during hwmon
initialization.

Bspec: 51864

v2: Add Bspec reference (Gwan-gyeong)
v3: Add Fixes tag

Fixes: 99f55efb

 ("drm/i915/hwmon: Power PL1 limit and TDP setting")
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230203155309.1042297-1-ashutosh.dixit@intel.com