ASoC: rt5665: force using PLL if MCLK is not suitable

Idealy PLL will be set in machine driver if MCLK doesn't meet the
requirement of codec. To let the codec driver be more general, we
can use a common PLL setting once sysclk/pll doesn't set properly
in machine driver.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>