ASoC: max98088: Fix enum ctl accesses in a wrong type

"EQ1 Mode" and "EQ2 Mode" ctls in max98088 codec driver are enum,
while the current driver accesses wrongly via value.integer.value[].
They have to be via value.enumerated.item[] instead.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>