dt-bindings: display: innolux,p097pfg: Document ports

dt-bindings: display: innolux,p097pfg: Document ports

This MIPI-DSI LCD panel must be connected to something.  According to
scarce web data it supports two channels and it is already used like
this in DTS.  Reported by dtbs_check:

  rockchip/rk3399-gru-scarlet-inx.dtb: panel@0 (innolux,p097pfg): 'ports' does not match any of the regexes: '^pinctrl-[0-9]+$'

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patch.msgid.link/20260306-dt-bindings-display-panel-clean-v1-2-3086eda1efaf@oss.qualcomm.com