[IA64] Avoid "u64 foo : 32;" for gcc3 vs. gcc4 compatibility

gcc3 thinks that a 32-bit field of a u64 type is itself a u64, so
should be printed with "%ld".  gcc4 thinks it needs just "%d".
Make both versions happy by avoiding this construct.

Signed-off-by: Tony Luck <tony.luck@intel.com>