mpc83xx: move CPU_TYPE_ENTRY over to processor.h

to avoid this:

cpu.c:47:1: warning: "CPU_TYPE_ENTRY" redefined
In file included from cpu.c:33:
/home/kim/git/u-boot/include/asm/processor.h:982:1: warning: this is the location of the previous definition

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>