Welcome to the forum.
They're are 2 safety switches 1 on the side stand and 1 on the clutch. It's the one on the clutch that locks out the transmission. Has to be in neutral or clutch pulled in to start. Disabling the clutch switch will allow the bike to push start but will also allow the starter to crank the bike in gear with predicable result!
The side stand switch can be problematic also, mine's disabled. I figure if you can't remember to put your stand up before you take off you probably shouldn't be riding in the first place!
To the best of my knowledge and belief, neither the clutch safety switch nor the side stand safety switch has any effect on bump-starting KLR's, even Gen 2's.
(As a test or demonstration, those with Gen 2 KLR's and functional clutch and kickstand safety switches can attempt a bump-start while coasting down a hill.)
With the ignition switch on, engine stop switch in RUN position, bike in gear (e.g., 3d gear), clutch disengaged, bike rolled and clutch popped, engine will turn over and bike engine will start (assuming operable engine condition), whether Gen 1 or 2.
Of course, in gear (neutral switch OPEN) with kickstand DOWN and functional kickstand safety switch (OPEN), ignition circuit is disabled--don't want to ride around with kickstand down anyway.
The neutral safety switch provides electrical continuity for the ELECTRIC starter circuit when the transmission is in neutral; is irrelevant to bump-starting a KLR, AFAIK
The switch logic can be traced on Gen 2's at RoberTX's wiring diagram.