ARM: 7909/1: mm: Call setup_dma_zone() post early_paging_init()

To get updated __pv_phys_offset, setup_dma_zone() needs to be
called after early_paging_init().

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>