Add serial console support for non-OF systems. There is a generic serial
console layer which calls a serial console driver. Included is the serial
console driver for the ns16550 class of uarts. Necessary support routines
are added as well.
Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
