drm/panel: st7701: Rename macros

Rename DSI_CMD* macros to ST7701_CMD*, and ST7701_DSI macro to
ST7701_WRITE, because they do not belong to DSI.
Signed-off-by: Hironori KIKUCHI <kikuchan98@gmail.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240804061503.881283-2-kikuchan98@gmail.comSigned-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240804061503.881283-2-kikuchan98@gmail.com