Revert "ARM: 7908/1: mm: Fix the arm_dma_limit calculation"

This reverts commit 787b0d5c1ca7ff24feb6f92e4c7f4410ee7d81a8 since
it is no longer required after 7909/1 was applied, and it causes
build regressions when ARM_PATCH_PHYS_VIRT is disabled and DMA_ZONE
is enabled.

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

arch/arm/mm/init.c

@@ -229,7 +229,7 @@ void __init setup_dma_zone(const struct machine_desc *mdesc)
 #ifdef CONFIG_ZONE_DMA
 	if (mdesc->dma_zone_size) {
 		arm_dma_zone_size = mdesc->dma_zone_size;
-		arm_dma_limit = __pv_phys_offset + arm_dma_zone_size - 1;
+		arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
 	} else
 		arm_dma_limit = 0xffffffff;
 	arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;