ia64: fix build failure caused by memory model changes

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Merge tag 'fixes-2021-01-18' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock

Pull ia64 build fix from Mike Rapoport:
 "Fix an ia64 build failure caused by memory model changes"

* tag 'fixes-2021-01-18' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
  ia64: fix build failure caused by memory model changes

arch/ia64/include/asm/sparsemem.h

@@ -3,6 +3,7 @@
 #define _ASM_IA64_SPARSEMEM_H
 
 #ifdef CONFIG_SPARSEMEM
+#include <asm/page.h>
 /*
  * SECTION_SIZE_BITS            2^N: how big each section will be
  * MAX_PHYSMEM_BITS             2^N: how much memory we can have in that space