drm/i915/pcode: Init pcode on different gt's

Extend pcode initialization to pcode on different gt's.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/4de1e4fd71a2971549c5cfb185412f190f15e235.1653484574.git.ashutosh.dixit@intel.com