mpc83xx: Size optimization of start.S

mpc83xx: Size optimization of start.S

Currently there are in excess of 100 bytes located at the beginning of the image
built by start.S that are not being utilized.  This patch moves a few functions
into this part of the image.  This will create a greater number of *available*
bytes that can be used by board specific code in NAND builds and will decrease
the size of the assembled code in other builds.

Signed-off-by: Ron Madrid <ron_madrid@sbcglobal.net>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>