[ARM] EBSA110: fix build errors caused by missing "const"

arch/arm/mach-ebsa110/io.c:106: error: conflicting types for 'readsw'
arch/arm/mach-ebsa110/io.c:116: error: conflicting types for 'readsl'
arch/arm/mach-ebsa110/io.c:161: error: conflicting types for 'writesw'
arch/arm/mach-ebsa110/io.c:171: error: conflicting types for 'writesl'

Signed-off-by: Russell King <[e-mail]>

arch/arm/mach-ebsa110/io.c

···
 EXPORT_SYMBOL(__readw);
 EXPORT_SYMBOL(__readl);
 
-void readsw(void __iomem *addr, void *data, int len)
+void readsw(const void __iomem *addr, void *data, int len)
 {
 	void __iomem *a = __isamem_convert_addr(addr);
 
···
 }
 EXPORT_SYMBOL(readsw);
 
-void readsl(void __iomem *addr, void *data, int len)
+void readsl(const void __iomem *addr, void *data, int len)
 {
 	void __iomem *a = __isamem_convert_addr(addr);
 
···
 EXPORT_SYMBOL(__writew);
 EXPORT_SYMBOL(__writel);
 
-void writesw(void __iomem *addr, void *data, int len)
+void writesw(void __iomem *addr, const void *data, int len)
 {
 	void __iomem *a = __isamem_convert_addr(addr);
 
···
 }
 EXPORT_SYMBOL(writesw);
 
-void writesl(void __iomem *addr, void *data, int len)
+void writesl(void __iomem *addr, const void *data, int len)
 {
 	void __iomem *a = __isamem_convert_addr(addr);