ARM: mach-sa1100: fix implicit use of page.h

Fixes this build error:

arch/arm/mach-sa1100/nanoengine.c:75:11: error: 'PAGE_SHIFT' undeclared here (not in a function)

CC: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>