[ARM] 5305/1: ARM: OMAP: Fix compile of McBSP by removing unnecessary check

Recent McBSP patches changed to allocating devices dynamically
and the check for OMAP_MAX_MCBSP_COUNT became unnecessary.

The check for OMAP_MAX_MCBSP_COUNT should have been removed with
the earlier McBSP patches in devices.c but was accidentally left
out.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>