drm/i915: Move the POWER_DOMAIN_AUX_IO_A definition to its logical place

Move the definition of the AUX_IO_A power domain, requiring only the
corresponding AUX_IO_A power well to be enabled, before all the
AUX_<port> power domains, which require both the AUX_IO_<port> and the
DC_OFF power wells to be enabled.

No functional change.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221114122251.21327-4-imre.deak@intel.com