x86: Export kmap_atomic_to_page()

Needed by KVM.
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/mm/highmem_32.c

@@ -104,6 +104,7 @@ EXPORT_SYMBOL(kunmap);
 EXPORT_SYMBOL(kmap_atomic);
 EXPORT_SYMBOL(kunmap_atomic);
 EXPORT_SYMBOL(kmap_atomic_prot);
+EXPORT_SYMBOL(kmap_atomic_to_page);
 
 void __init set_highmem_pages_init(void)
 {