Fix crash when using flint and steel on creeper

mods/ENTITIES/mcl_mobs/api.lua

@@ -213,11 +213,11 @@ end
 local collision = function(self)
 
 	local pos = self.object:get_pos()
+	if not pos then return {0,0} end
 	local vel = self.object:get_velocity()
 	local x = 0
 	local z = 0
 	local width = -self.collisionbox[1] + self.collisionbox[4] + 0.5
-
 	for _,object in pairs(minetest.get_objects_inside_radius(pos, width)) do
 
 		local ent = object:get_luaentity()
@@ -254,13 +254,15 @@ local set_velocity = function(self, v)
 	end
 
 	local yaw = (self.object:get_yaw() or 0) + self.rotate
-
+	local vv = self.object:get_velocity()
+	if vv then
 		self.object:set_velocity({
 			x = (sin(yaw) * -v) + c_x,
-		y = self.object:get_velocity().y,
+			y = vv.y,
 			z = (cos(yaw) * v) + c_y,
 		})
 	end
+end
 
 
 
@@ -3002,6 +3004,7 @@ end
 
 local function check_entity_cramming(self)
 	local p = self.object:get_pos()
+	if not p then return end
 	local oo = minetest.get_objects_inside_radius(p,1)
 	local mobs = {}
 	for _,o in pairs(oo) do