Small suggestion

[Leon Pollak]

Hello,
	I encountered the following situation: while debugging my new MPC860 BSP code 
I decided to start without MMU in order to avoid possible problems at the 
first stage.
	Thus, the MMU_N_TLB_TableEntries variable is zero.
	The mmu.c file in .../libcpu/powerpc/mpc8xx/mmu directory avoids to fill 
MMU_TLB table, because there is for-loop till MMU_N_TLB_TableEntries, but 
still attempts to turn on address translation.
	May be it will be useful to put the last 3 operators in the file mmu.c inside
	if (MMU_N_TLB_TableEntries) {
		Turn Translation On;
	}
Thanks
-- 
leonp at plris dot com