ALSA: HDA VIA: Remove unused IS_VT17xx_VENDORID macro

IS_VT17*_VENDORID macros are used nowhere, so clean them up.

Signed-off-by: Lydia Wang <lydiawang@viatech.com.cn>
Signed-off-by: Logan Li <loganli@viatech.com.cn>
Signed-off-by: Takashi Iwai <tiwai@suse.de>