treewide: remove references to CREDITS ...

The CREDITS file was removed from barebox in 2015 by commit 6570288f2d97
("Remove the CREDITS file"). Remove references to it from several files.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

video: simple-panel: Add support for device tree provided nodes ...

This adds support for display timings provided from device tree.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

video: simple-panel: Add debug/error messages ...

Let the driver be more informative when something goes wrong.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

video: simple-panel: mode support depends on I2C and EDID ...

Reading modes from EDID EEPROMs requires both I2C and EDID support to
be available. As the simple panel driver is also useful without mode
reading support, only built it in if the requirements are met.

Fixes:
In function `simple_panel_get_modes':
simple-panel.c:88: undefined reference to `of_find_i2c_adapter_by_node'
simple-panel.c:91: undefined reference to `edid_read_i2c'
simple-panel.c:95: undefined reference to `edid_to_display_timings'

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

video: Add simple-panel support ...

This adds support for simple panels. These are panels which don't need
special handling but can have enable gpios and such. Unlike the Linux
kernel implementation this one is able to understand display-timings
nodes so that it's not necessary to keep a list of all known displays
with their corresponding timings in barebox.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>