[IA64] Build fix for __early_pfn_to_nid() undefined link error
ia64 only defines __early_pfn_to_nid() for SPARSEMEM && NUMA configurations,
so the recent:
commit: f2dbcfa738368c8a40d4a5f0b65dc9879577cb21
mm: clean up for early_pfn_to_nid()
ends up with some link problems for certain configuration files.
Fix arch/ia64/Kconfig to only define HAVE_ARCH_EARLY_PFN_TO_NID in the
cases where we do provide this function.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Tony Luck