CRIS: Define io_remap_pfn_range as remap_pfn_range

CRIS don't need any special mapping for io, but didn't define this,
meaning that all uses of io_remap_pfn_range lead to compile errors.

This fixes a compile error introduced in CRIS when drivers/mtd/mtdchar.c
mmap handling was changed in commit dd02b67dSigned-off-by: Jesper Nilsson <jesper.nilsson@axis.com>

arch/cris/include/asm/pgtable.h

@@ -260,6 +260,9 @@ static inline pgd_t * pgd_offset(const struct mm_struct *mm, unsigned long addre
 #define pgd_ERROR(e) \
         printk("%s:%d: bad pgd %p(%08lx).\n", __FILE__, __LINE__, &(e), pgd_val(e))
 
+#define io_remap_pfn_range(vma, vaddr, pfn, size, prot)         \
+		remap_pfn_range(vma, vaddr, pfn, size, prot)
+
 
 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* defined in head.S */