input_cmd_xkb_switch_layout: support input types
input_cmd_xkb_switch_layout: support input types

This just adds input type config support to input_cmd_xkb_switch_layout
so that `input type:keyboard xkb_switch_layout <idx>` will work

ascent12/sway,1ace/sway,ascent12/sway,ascent12/sway,1ace/sway,SirCmpwn/sway,1ace/sway