The "powerpc/shared/console" code has the start-up console value fixed
at 9600 baud. This changes the hard-wired constant "9600" in the code
to the configuration setting "BSP_CONSOLE_BAUD" and adds configuration
support in both the "waf" and the legacy configuration systems.
Note that the VME BSPs beatnik, mvme3100, and mve5100 can be improved
by adding a "mvmexxxx" BSP family. This configuration change, as well
as future configuration changes, could then be made in a "grp.yml" file.
