OMAP/serial: Fix Mode13 vs Mode16 priority

Make Mode16 more preferred than Mode13, to match TRM baudrates table.

Signed-off-by: Alexey Pelykh <alexey.pelykh@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>