Using a resistor the same value as the ignition switch's is bettter of the two. If you put a toggle switch in it your passlock light will be on all the time when the engines running, and if you unhook the battery you will have to start it with the cylinder's passlock switched on. But what if the cylinder's passlock quick working by that point? You would have to quess what resistor value to use and install a resistor anyway, or replace the ignition switch.
Replacing the ignition switch is the "proper way" of fixing the problem in the first place btw. This all assumes that it's the switch acting up, which is usually the case. But it's also possible to have a wiring problem or BCM problem that's causing the passlock to act up.