ARM: OMAP1: DMA: Correct the number of logical channels

OMAP1510, OMAP5910 and OMAP310 have only 9 logical channels.
OMAP1610, OMAP5912, OMAP1710, OMAP730, and OMAP850 have 16 logical channels
available.

The wired 17 for the lch_count must have been used to cover the 16 + 1
dedicated LCD channel, in reality we can only use 9 or 16 channels.

The d->chan_count is not used by the omap-dma stack, so we can skip the
setup. chan_count was configured to the number of logical channels and not
the actual number of physical channels anyways.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Tony Lindgren <tony@atomide.com>