drm/i915/dsi: pass display to register macros instead of implicit variable

Stop relying on the dev_priv local variable in the DSI register
macros. Pass struct intel_display pointer to the macros. Move the MIPI
DSI MMIO base selection to a different level, passing it to _MMIO_MIPI()
and doing the addition there.

Start using the local display variable for all intel_de_* usage, and
opportunistically use it for other things than display registers as
well.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/6dd52f3fce3527242479aadc276d05de74ceae5d.1713520813.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>