Stop call waiting timers after waiting call accepted

After user accepted CDMA waiting call, remove call waiting timers.

Change-Id: I1b9f3036c07aee2e14528e05573bd1b106f9a31f
CRs-Fixed: 673246
CSVT: fix cannot end videocall issues after NFC read contact and lauch another call
      when CSVT call is active back ground
      CRs-Fixed: 678578

Change-Id: I1b0aff348a6d01d7648d1a754ae6168af270f3c4