ASoC: arizona: Move notifier functions to header and make inline

These functions are very thin wrappers around core functions, so they
make sense as inline functions.  Also making them inline avoids build
issues in the case where the machine driver is built in but the CODEC
is built as a module.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>