ARM: OMAP: mcbsp: Move out omap_mcbsp_register_board_cfg from plat-omap/devices.c

Only OMAP1s are using omap_mcbsp_register_board_cfg after OMAP2+ hwmod
conversion so it can be moved to mach-omap1/mcbsp.c.

Signed-off-by: Jarkko Nikula <jarkko.nikula@bitmer.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Tony Lindgren <tony@atomide.com>