ia64: export memory_add_physaddr_to_nid to fix cxl build error

cxl_pmem.ko uses memory_add_physaddr_to_nid() but ia64 does not export it,
so this causes a build error:

ERROR: modpost: "memory_add_physaddr_to_nid" [drivers/cxl/cxl_pmem.ko] undefined!

Fix this by exporting that function.

Fixes: 8c2676a ("hot-add-mem x86_64: memory_add_physaddr_to_nid node fixup")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Randy Dunlap <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Ben Widawsky <[email protected]>
Cc: Jonathan Cameron <[email protected]>
Cc: [email protected]
Cc: Arnd Bergmann <[email protected]>
Cc: Keith Mannthey <[email protected]>
Cc: Andrew Morton <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>

Author: rddunlap

arch/ia64/mm/numa.c

@@ -75,5 +75,6 @@ int memory_add_physaddr_to_nid(u64 addr)
 		return 0;
 	return nid;
 }
+EXPORT_SYMBOL(memory_add_physaddr_to_nid);
 #endif
 #endif