Add permitted_packages to framework-tethering.

(cherry picked from commit 577707e0)

Test: m out/soong/.intermediates/frameworks/base/packages/Tethering/common/TetheringLib/framework-tethering/android_common/package-check.stamp
Bug: 151314205
Merged-In: I248c36b2cf2f5776978c4fd2322d3b73ade309ff
Change-Id: Iddeeb6648f1ed2a31eebf04eb465ea675fb610ae

Tethering/common/TetheringLib/Android.bp

@@ -60,6 +60,7 @@ java_library {
     hostdex: true, // for hiddenapi check
     visibility: ["//frameworks/base/packages/Tethering:__subpackages__"],
     apex_available: ["com.android.tethering"],
+    permitted_packages: ["android.net"],
 }
 
 stubs_defaults {