Added permission check for setCellInfoListRate

Now the caller needs to have MODIFY_PHONE_STATE to call
this API.

Test: Manual
bug: 33815946
Change-Id: Ia2cf0de383572033c70b94ae71080ef35c3f443c
(cherry picked from commit 3128d9ec40fadccbf2be7b9e962e35b9bfbc003a)
(cherry picked from commit 24ea27a2758f753b6e132b2c424f6bfb6c52c774)
diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index 45bea8a..9c6adb3 100644
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -1633,6 +1633,7 @@
 
     @Override
     public void setCellInfoListRate(int rateInMillis) {
+        enforceModifyPermission();
         mPhone.setCellInfoListRate(rateInMillis);
     }