adv7511 probe may need to be attempted multiple times before no
-EPROBE_DEFER is returned. Currently, every such probe results in
an error message:

[    4.534229] adv7511 1-003d: failed to find dsi host
[    4.580288] adv7511 1-003d: failed to find dsi host

This is misleading, as there is no error and probe deferral is normal
behavior. Fix this by using dev_err_probe that will suppress
-EPROBE_DEFER errors. While at it, we touch all dev_err in the probe
path. This makes the code more concise and included the error code
everywhere to aid user in debugging.
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221026125246.3188260-1-a.fatoum@pengutronix.de