[IA64] Fix build for sim_defconfig

Commit bdc80787

 broke the build
for this config because the sim_defconfig selects CONFIG_HZ=250
but include/asm-ia64/param.h has an ifdef for the simulator to
force HZ to 32.  So we ended up with a kernel/timeconst.h set
for HZ=250 ... which then failed the check for the right HZ
value and died with:

Drop the #ifdef magic from param.h and make force CONFIG_HZ=32
directly for the simulator.

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