ASoC: ti: omap3pandora: update board check to use DT compatible

ASoC: ti: omap3pandora: update board check to use DT compatible

The omap3pandora driver contains a check for the ARM machine ID via the
machine_is_omap3_pandora() macro. The board concerned now supports
only FDT booting, which does not use machine IDs, and therefore the
code should be updated to check the DT compatible property instead. The
legacy board file for this machine was removed in commit 7fcf7e061edd
("ARM: OMAP2+: Remove legacy booting support for Pandora").
The presence of this machine ID check prevents the removal of machine
IDs no longer used by the kernel from arch/arm/tools/mach-types,
because the machine_is_*() macros are generated from mach-types. To
resolve this issue, use of_machine_is_compatible() instead.

Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
Acked-by: Jarkko Nikula <jarkko.nikula@bitmer.com>
Signed-off-by: Mark Brown <broonie@kernel.org>