conf: topology: Fix index mismatch for skl and bxt

The topology index in the conf is set to 1, where the driver expects index
set to 0. Fix the inconsistency.

Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>