ARM: dts: imx6qdl-colibri: Update audio card name

ARM: dts: imx6qdl-colibri: Update audio card name

Update the audio card name for Colibri iMX6 to match its specific SoM
name, making it less than 15 characters to fix the following warning

fsl-asoc-card sound: ASoC: driver name too long
'imx6dl-colibri-sgtl5000' -> 'imx6dl-colibri-'

making it compliant with the ALSA configuration specification [1].

While this is a breaking change for userspace tooling, it seems
time to implement it since no ALSA UCM or related configuration files
currently exist and we are in the the process of creating them.

[1] Documentation/sound/alsa-configuration.rst

Signed-off-by: Hiago De Franco <hiago.franco@toradex.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>