video: ssd1307fb: Use gpiod_set_value_cansleep() for reset

The reset signal can be produced by GPIO expander that can sleep.
In that case the probe function fails. Allow using GPIO expanders for
the reset signal by using the non-atomic gpiod_set_value_cansleep()
function.

Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>