ASoC: wm8962: Turn on regcache_cache_only before disabling regulator

It's safer to turn on regcache_cache_only before disabling regulator since
the driver will turn off the regcache_cache_only after enabling regulator.

If we remain cache_only false, some command like 'amixer cset' would get
failure if being run before wm8962_resume().

Signed-off-by: Nicolin Chen <b42378@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org