When the line-out jack is plugged/unplugged, the driver needs to check
the headphone plug, not only the line-out jack itself.  Otherwise the
headphone or the speaker may be wrongly muted/unmuted.

As a result, both STAC_HP_EVENT and STAC_LO_EVENT need to call the
same function, stac92xx_hp_detect().
Signed-off-by: Takashi Iwai <tiwai@suse.de>