Add privapp permissions for DeviceDiagnostics

Bug: 309886423
Test: See imei in DeviceDiagnostics attestation details
Change-Id: I326a0cc834eb2ac605a91cc50d5dfe8f81ea3adf

data/etc/privapp-permissions-platform.xml

@@ -605,4 +605,8 @@ applications that come with the platform
     <privapp-permissions package="com.android.calllogbackup">
         <permission name="com.android.voicemail.permission.READ_VOICEMAIL"/>
     </privapp-permissions>
+
+   <privapp-permissions package="com.android.devicediagnostics">
+        <permission name="android.permission.READ_PRIVILEGED_PHONE_STATE"/>
+    </privapp-permissions>
 </permissions>