ARC: export kmap

|  MODPOST 7 modules
| ERROR: "kmap" [fs/ext2/ext2.ko] undefined!
| ../scripts/Makefile.modpost:91: recipe for target '__modpost' failed

Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/mm/highmem.c

@@ -61,6 +61,7 @@ void *kmap(struct page *page)
 
 	return kmap_high(page);
 }
+EXPORT_SYMBOL(kmap);
 
 void *kmap_atomic(struct page *page)
 {