tty: vt: selection: Correct misspelled function sel_loadlut()

tty: vt: selection: Correct misspelled function sel_loadlut()

Fixes the following W=1 kernel build warning(s):

 drivers/tty/vt/selection.c:119: warning: expecting prototype for set loadlut(). Prototype was for sel_loadlut() instead

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210520121906.3468725-2-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>