Fix typo in the _SEL_FETCH_PLANE_BASE_1_B register base address.

Fixes: a5523e2f ("drm/i915: Add PSR2 selective fetch registers")
References: https://gitlab.freedesktop.org/drm/intel/-/issues/5400
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: <stable@vger.kernel.org> # v5.9+
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220421162221.2261895-1-imre.deak@intel.com