OMAPDSS: HDMI: OMAP4: Remap speaker order to match ALSA order

As of today, the only know user of the DSS HDMI audio support is
ASoC. Hence, it makes sense to remap the speaker order to match
the ALSA speaker order. In the future, a dynamic mapping mechanism
may be implemented.

Remapping is needed as the HDMI speaker order is FL/FR/LFE/C/RL/RR/
RLC-FLC/RRC-FLC while the ALSA order is FL/FR/RL/RR/C/LFE/SL/SR.
Refer to CEA-861 Section 6.6.2 for further details.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>