ASoC: fsl-ssi: add SSIEN errata work around

The chip errata for the i.MX35, Rev.2 has the following errata:

ENGcm06222: SSI:Transmission does not take place in bit length early frame sync
	    configuration

The workaround states, that TX_EN and SSI_EN bits should be set in the same
register write. As the next errata in the document (ENGcm06532) says to always
write RX_EN and TX_EN in the same register write in network mode.

Therefore include the whole write to
	CCSR_SSI_SCR_TE and CCSR_SSI_SCR_RE
into the write to
	CCSR_SSI_SCR_SSIEN

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>