remove superfluous check for input_type
remove superfluous check for input_type

This condition is already enforced in grab_all_keys().

i3/i3,avrelaun/i3,Airblader/i3,strake/i3,stapelberg/i3,stapelberg/i3,shdown/i3,stapelberg/i3,i3/i3,Airblader/i3-original,avrelaun/i3,avrelaun/i3,strake/i3,acrisci/i3,stapelberg/i3,i3/i3,strake/i3,i3/i3,cornerman/i3,Airblader/i3,cornerman/i3,cornerman/i3,Airblader/i3-original,EvilPudding/i3,Airblader/i3-original,cornerman/i3,shdown/i3,Airblader/i3-original,Airblader/i3-original,acrisci/i3,acrisci/i3,Airblader/i3,EvilPudding/i3,strake/i3,shdown/i3,shdown/i3,acrisci/i3,strake/i3,acrisci/i3,EvilPudding/i3,Airblader/i3,EvilPudding/i3,avrelaun/i3