Hide "Wipe eUICC" option when it isn't useful.

If a user never downloaded a profile onto their eUICC, there's no
reason to offer the wipe option, and it would only cause confusion.
But show the option nonetheless if developer options are enabled.

Bug: 38460669
Test: TreeHugger / Unit test / Manual verification
Change-Id: I51fb7b9e75c4f9a46ee0b24e64bddfafcbd48b14