The GPIO pin number for the mute LED control on HP laptops can be
determined more easily by checking the number of available GPIO pins
of the codec chip.  On a small package with up to 3 GPIOs, GPIO 0 is
used while GPIO 3 is used for others.

This fixes the missing mute GPIO for some HP laptops with new codecs.
Signed-off-by: Takashi Iwai <tiwai@suse.de>