[ALSA] ASoC AT91xxxx - SSC port DSP support

This patch series by Frank Madarino updates the AT91xxxx core to add
DSP/PCM audio hardware formats.
Changes:-
 o Rename at19-i2s.c -> at91-ssc.c
 o Rename at91-i2s.h -> at91-ssc.h
 o Add DSP hardware formats.
 o Rename various I2S labels to SSC

Signed-off-by: Frank Mandarino <fmandarino@endrelia.com>
Signed-off-by: Liam Girdwood <lg@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>