Different iface and ws_face.ident in AnodePlane.cxx for SBND

[HaiwangYu]

@weihythu and @ebelchio12 found these two lines are incompatible:
https://github.com/WireCell/wire-cell-toolkit/blob/master/gen/src/AnodePlane.cxx#L175 (should use ws_face.ident)
https://github.com/WireCell/wire-cell-toolkit/blob/master/img/src/GridTiling.cxx#L95

First one is wrong when iface != ws_face.ident, which is the SBND APA1 case (iface=0, ws_face.ident=1).

Also this seems to be wrong for SBND APA1
https://github.com/WireCell/wire-cell-toolkit/blob/master/gen/src/AnodePlane.cxx#L294
acoording to convention here:
https://github.com/WireCell/wire-cell-toolkit/blob/master/iface/inc/WireCellIface/IAnodeFace.h#L35-L38
While simple search suggests this which() is actually not used: