@Wiseguy You could do this, but personally, I think it's better to not have to worry about it each time I load up the map.
Also, this command would work better:
ent_fire func_door kill; ent_fire func_door_rotating kill; ent_fire prop_door_rotating kill

Another way to get rid of doors if you have sv_cheats 1 and are an admin

Type in console
ent_fire func_door kill
ent_fire func_door_rotating kill
ent_fire prop_door_rotating kill
This'll delete all door entities in the current map.