ioplug - Fix the refinement of period_* after periods
ioplug - Fix the refinement of period_* after periods

When changing only PERIODS after BUFFER_*, ioplug doesn't update
the corresponding PERIOD_* parameters properly.  This should fix
ALSA bug#2601.

mikelima/alsa-lib,zedongchen/alsa-lib,lgirdwood/alsa-lib,zedongchen/alsa-lib,gittup/alsa-lib,alsa-project/alsa-lib,alsa-project/alsa-lib,tiwai/alsa-lib,tiwai/alsa-lib,mengdonglin/alsa-lib,lgirdwood/alsa-lib,Distrotech/alsa-lib,takaswie/alsa-lib,tiwai/alsa-lib,gittup/alsa-lib,zedongchen/alsa-lib,mengdonglin/alsa-lib,takaswie/alsa-lib,Distrotech/alsa-lib,Distrotech/alsa-lib,gittup/alsa-lib,takaswie/alsa-lib,mengdonglin/alsa-lib,Distrotech/alsa-lib,mengdonglin/alsa-lib,takaswie/alsa-lib,Distrotech/alsa-lib,takaswie/alsa-lib,alsa-project/alsa-lib,gittup/alsa-lib,mikelima/alsa-lib,lgirdwood/alsa-lib,mengdonglin/alsa-lib,lgirdwood/alsa-lib,tiwai/alsa-lib,zedongchen/alsa-lib,lgirdwood/alsa-lib,mikelima/alsa-lib,mikelima/alsa-lib,alsa-project/alsa-lib,mikelima/alsa-lib,zedongchen/alsa-lib