Not send switch intents if there is no real intent

When resolving activtities for the USB device/accessory connection UI a
special intent that allows to switch between profiles get added. This
also gets added if there is no activity in the secondary profile that
can be started.

Fixes: 36544815
Test: Added work profile. Add USB handling app only to personal profile
      and plugged in USB device -> no crash anymore

Change-Id: I311ddd53b3ff0c8406e62bac57972d4b790ebddc