[ARM] Re-jig bootmem initialisation

Make ARM independent of the way bootmem operates internally.  We
now map each node as we initialise it, and place the bootmem bitmap
inside each node, rather than all in the first node.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --cc arch/arm/mm/init.c
Simple merge

diff --cc arch/arm/mm/mm-armv.c
Simple merge