B2OC: Reduce rate of Xib2Dph lines

Reduce rate of Xib2Dph lines:

• XibmToDmPK_DmToHHH
• XibmToDmPPi_DmToHHH
• XibmToDsmPK_DsmToHHH
• XibmToDsmPPi_DsmToHHH
• XibmToDstmPK_DstmToD0Pi_D0ToHH
• XibmToDstmPPi_DstmToD0Pi_D0ToHH

Stop using all HH or HHH decays and use only CF decays, i.e.

D^+ \to K^- \pi^+ \pi^+

,

D_s^+ \to K^+ K^- \pi^+

,

D^0 \to K^- \pi^+

.

Tighten the PID on all tracks, including adding a (PIDK - PIDp) cut to protons.

cc: @mwhitehe