[Provider Model] Fix the condition about admin user

Only the user is admin AND the admin is allowed to config mobile network

Bug: 196020201
Test: manual
Change-Id: I566dfa7585ade8fcba53a6a98213776e156267bd
Merged-In: I566dfa7585ade8fcba53a6a98213776e156267bd
(cherry picked from commit 0906d57b)