On the STMPE2401 and STMPE2401 altfunction 1 corresponds to the
PWM channels. This oneliner was missing in the case-switch, making
it impossible to enable the PWM channel output.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>