Revert "Fix the crash when editing or deleting APN."

This reverts commit db9a9bb0.

Reason for revert: As per discussion in b/72484718, we are going to
block Access Point Name entry point in Network&Settings, so we no longer
need the change in ApnSettings fragment itself.
Bug: 72484718

Change-Id: Ia84f129b86fe72b3b2dc9699d5893ced7c65e1c3