omap: Fix build after merging in hwmod support for testing

I've merged in the hwmod support from Kevin's tree for omap2+ machines,
so you need to update your serial port names to use ttyO instead of ttyS:

- u-boot bootargs for kernel cmdline needs to change with setenv
- if you use hardcoded CONFIG_CMDLINE, change it in your .config
- /etc/inittab in your omap root file system if using serial console

This should not affect omap1 machines. Please test and post issues
to the linux-omap mailing list!

Signed-off-by: Tony Lindgren <tony@atomide.com>