SAP: fix the crash due to PendingIntent flag setting

Android S+ taget to specify explicitly either FLAG_MUTABLE or
FLAG_IMMUTABLE when creating a PendingIntent. setNotificaion function
already set the FLAG_IMMUTABLE flag inside, so it doesn't need to add
FLAG_MUTABLE_UNAUDITED flag with the input paramters temporarily.

Bug: 175659870
Test: manual
Tag: #stability
Change-Id: I0b48f2ef828f7d3a67ce259acae5b7b5b8a7a79e