bta_dm: Don't clear scheduled service discovery on BTA_DmSearchCancel()

This function suppose to clear scheduled devices discovery or inquire
and not scheduled service discovery

Problem can be visible when pairing coorinated set and could end up with
one device being bonded but without any services connected.

Bug: 247511422
Bug: 242645864
Test: atest BluetoothInstrumentationTests
Tag: #feature

Change-Id: I83f55a173a17544c1a736a8218b769b038b9eecc