drm: bridge: icn6211: Register macro clean up

Drop two unused register macros, ICN6211_MAX_REGISTER and MIPI_ATE_STATUS_1,
neither of which is used and where the later should be specified using macro
MIPI_ATE_STATUS(1) instead. Drop the _(n) underscore and keep only the (n)
part of register macros. No functional change.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
To: dri-devel@lists.freedesktop.org
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220430025020.640277-1-marex@denx.de