ALSA: hda - fix typo in proc output

commit aeb3a97222832e5457c4b72d72235098ce4bfe8d upstream.

Rename "Digitial In" to "Digital In". This function is only used for
proc output, so should not cause any problems to change.

Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>