le_impl: Fix for unnecessary connect cancel

With this patch connection manager will not cancel create connection when
device which is trying to connect is already connecting with high scan
paramerters e.g. when direct connect is called after direct connect or
background connect is done after direct connect

Bug: 356594223
Bug: 356593752
Test: atest bluetooth_gd_unit_test
Flag: com.android.bluetooth.flags.improve_create_connection_for_already_connecting_device

Change-Id: I4083381b9f516d07044b3d47f5c74e92331a27d6