Bump to minapi 28

mobile/src/main/java/be/mygod/vpnhotspot/net/TetherOffloadManager.kt

@@ -1,10 +1,8 @@
 package be.mygod.vpnhotspot.net
 
-import android.os.Build
 import android.provider.Settings
 import be.mygod.vpnhotspot.App.Companion.app
 import be.mygod.vpnhotspot.root.SettingsGlobalPut
-import timber.log.Timber
 
 /**
  * It's hard to change tethering rules with Tethering hardware acceleration enabled for now.
@@ -15,19 +13,6 @@ import timber.log.Timber
  *   https://android.googlesource.com/platform/hardware/qcom/data/ipacfg-mgr/+/master/msm8998/ipacm/src/IPACM_OffloadManager.cpp
  */
 object TetherOffloadManager {
-    val supported by lazy {
-        Build.VERSION.SDK_INT >= 27 || try {
-            Settings.Global::class.java.getDeclaredField("TETHER_OFFLOAD_DISABLED").get(null).let {
-                require(it == TETHER_OFFLOAD_DISABLED) { "Unknown field $it" }
-            }
-            true
-        } catch (_: NoSuchFieldException) {
-            false
-        } catch (e: Exception) {
-            Timber.w(e)
-            false
-        }
-    }
     private const val TETHER_OFFLOAD_DISABLED = "tether_offload_disabled"
     val enabled get() = Settings.Global.getInt(app.contentResolver, TETHER_OFFLOAD_DISABLED, 0) == 0
     suspend fun setEnabled(value: Boolean) = SettingsGlobalPut.int(TETHER_OFFLOAD_DISABLED, if (value) 0 else 1)