Change slot to subId to support crossSimDuplicateDetection am: a9657fa25e

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/CellBroadcastService/+/25369171

Change-Id: I0144e2d5ef06f08f6f648a8c555effcb95f60f42
Signed-off-by: Automerger Merge Worker <[email protected]>