ARM: dma-mapping: Add missing static storage class specifier

Fixes the following sparse warnings:
arch/arm/mm/dma-mapping.c:231:15: warning: symbol 'consistent_base' was not
declared. Should it be static?
arch/arm/mm/dma-mapping.c:326:8: warning: symbol 'coherent_pool_size' was not
declared. Should it be static?

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

arch/arm/mm/dma-mapping.c

@@ -228,7 +228,7 @@ static pte_t **consistent_pte;
 
 #define DEFAULT_CONSISTENT_DMA_SIZE SZ_2M
 
-unsigned long consistent_base = CONSISTENT_END - DEFAULT_CONSISTENT_DMA_SIZE;
+static unsigned long consistent_base = CONSISTENT_END - DEFAULT_CONSISTENT_DMA_SIZE;
 
 void __init init_consistent_dma_size(unsigned long size)
 {
@@ -321,7 +321,7 @@ static struct arm_vmregion_head coherent_head = {
 	.vm_list	= LIST_HEAD_INIT(coherent_head.vm_list),
 };
 
-size_t coherent_pool_size = DEFAULT_CONSISTENT_DMA_SIZE / 8;
+static size_t coherent_pool_size = DEFAULT_CONSISTENT_DMA_SIZE / 8;
 
 static int __init early_coherent_pool(char *p)
 {