ARM: fix IXP4xx build failure

arm: export dma_set_coherent_mask

While a regression was fixed with commit 710224fa2750cf (arm: fix
"arm: fix pci_set_consistent_dma_mask for dmabounce devices"), a
new one was introduced as dma_set_coherent_mask wasn't exported
for modules. This patch takes care for this issue.

Signed-off-by: Imre Kaloz <kaloz@openwrt.org>
Signed-off-by: Krzysztof HaƂasa <khc@pm.waw.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/arm/common/it8152.c b/arch/arm/common/it8152.c
index 1bec96e..42ff90b 100644
--- a/arch/arm/common/it8152.c
+++ b/arch/arm/common/it8152.c
@@ -352,3 +352,4 @@
 	return pci_scan_bus(nr, &it8152_ops, sys);
 }
 
+EXPORT_SYMBOL(dma_set_coherent_mask);