Need include "asm/types.h", just like arm has done, or can not pass
compiling, the related error:

  In file included from arch/arm64/include/asm/page.h:37:0,
                   from drivers/staging/lustre/include/linux/lnet/linux/lib-lnet.h:42,
                   from drivers/staging/lustre/include/linux/lnet/lib-lnet.h:44,
                   from drivers/staging/lustre/lnet/lnet/api-ni.c:38:
  arch/arm64/include/asm/pgtable-2level-types.h:19:1: error: unknown type name ‘u64
  arch/arm64/include/asm/pgtable-2level-types.h:20:1: error: unknown type name ‘u64’
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>