configs: nexbox_a95x_defconfig: bump to kernel 4.12

configs: nexbox_a95x_defconfig: bump to kernel 4.12

Main difference is that the drm driver now supports the hdmi output.

The gxl variant device tree has been renamed in:

commit 7eea67101b9713ae438955e8899b3c4b078419f9
Author: Kevin Hilman <khilman@baylibre.com>
Date:   Fri Jan 20 07:57:52 2017 -0800

    ARM64: dts: meson-gxl: rename Nexbox A95x for consistency

    Since the GXL family has S905X and S905D SoCs, we're keeping the SoC
    name in the DTS filename for clarity.  Rename this file accordingly to
    be consistent with the rest of the GXL DTS files.

    Cc: Neil Armstrong <narmstrong@baylibre.com>
    Reviewed-by: Andreas Färber <afaerber@suse.de>
    Signed-off-by: Kevin Hilman <khilman@baylibre.com>
So adjust the defconfig and boot script to match.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>