[IA64] refresh config files

Bring defconfig, tiger_defconfig and zx1_defconfig up to date. Also
sprinkle KEXEC and KDUMP combinations around liberally so that my
usual regression test builds will see all combinations:

 tiger_defconfig gets KEXEC=y, CRASH_DUMP=n
 zx1_defconfig   gets KEXEC=n, CRASH_DUMP=y
 defconfig       gets KEXEC=y, CRASH_DUMP=y
 others remain at     KEXEC=n, CRASH_DUMP=n

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