Add more de helpers to be able to avoid direct calls to uncore.

v3 by Jani:
- drop intel_de_write_samevalue/intel_de_rewrite_fw altogether

v2 by Jani:
- drop pcode stuff for now
- rename intel_de_write_samevalue -> intel_de_rewrite_fw

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/0d051554dfeeb4d8aa3bc9136ed111fa35f647d8.1670433372.git.jani.nikula@intel.com