Creation of mpc6xx_machdep.c

[Matt Thomas <matt%3am-software.com@localhost>]

Today, I'm planning on create arch/powerpc/mpc6xx/mpc6xx_machdep.c and
incorporating much of the redundant code from mpc6xx-based port's
machdep.c.

Primary of these is the initialization of the vector table (including
installing the external interrupt h.  But I will the include the
initialization of the bat registers as well.  I'll also move dumpsys.

My primary reason for doing this is to prepare for the addition of
Altivec support and I'd like to only change each port once.

--
Matt Thomas               Internet:   matt%3am-software.com@localhost
3am Software Foundry      WWW URL:    http://www.3am-software.com/bio/matt/
Cupertino, CA             Disclaimer: I avow all knowledge of this message