Update permission check for offloadEngine registration

For an app to register itself as an offloadEngine, it must have either
of the following permissions: NETWORK_STACK,
PERMISSION_MAINLINE_NETWORK_STACK, NETWORK_SETTINGS,
REGISTER_NSD_OFFLOAD_ENGINE.

Bug: 294777050
Test: atest CtsNetTestCases FrameworksNetTests
Change-Id: I19fe9b996a02b1ae23116c02a1b8406d93b3ecf1