ARM: use phys_addr_t for DMA zone sizes

In order to specify a DMA zone size of 4GB on LPAE systems, the sizes need
to be 64-bit. So make machine_desc.dma_zone_size and arm_dma_zone_size be
phys_addr_t instead of unsigned long.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>

arch/arm/include/asm/mach/arch.h

@@ -35,7 +35,7 @@ struct machine_desc {
 	unsigned int		nr_irqs;	/* number of IRQs */
 
 #ifdef CONFIG_ZONE_DMA
-	unsigned long		dma_zone_size;	/* size of DMA-able area */
+	phys_addr_t		dma_zone_size;	/* size of DMA-able area */
 #endif
 
 	unsigned int		video_start;	/* start of video RAM	*/

arch/arm/mm/init.c

@@ -207,7 +207,7 @@ static void __init arm_bootmem_init(unsigned long start_pfn,
 
 #ifdef CONFIG_ZONE_DMA
 
-unsigned long arm_dma_zone_size __read_mostly;
+phys_addr_t arm_dma_zone_size __read_mostly;
 EXPORT_SYMBOL(arm_dma_zone_size);
 
 /*