[ALSA] soc at91 minor bug fixes

Found these two bugs while browsing through the code.  The first one is
a cut-n-paste bug, instead of disabling the clock when request_irq()
fails, it enabled it once more.  The second one fixes a debug printout,
AT91_SSC_IER is write only, AT91_SSC_IMR is readable (the printed string
actually says imr).

Frank Mandarino was busy so he asked me to send these to this list.

/Patrik

Signed-off-by: Patrik Sevallius <patrik.sevallius@enea.com>
Acked-by: Frank Mandarino <fmandarino@endrelia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>