constify JNINativeMethod function pointer tables

Change-Id: I4036c924958221cbc644724f8eb01c5de3cd7954
diff --git a/media/jni/android_mtp_MtpDatabase.cpp b/media/jni/android_mtp_MtpDatabase.cpp
index 713f28c..ec2f98a 100644
--- a/media/jni/android_mtp_MtpDatabase.cpp
+++ b/media/jni/android_mtp_MtpDatabase.cpp
@@ -1173,12 +1173,12 @@
 
 // ----------------------------------------------------------------------------
 
-static JNINativeMethod gMtpDatabaseMethods[] = {
+static const JNINativeMethod gMtpDatabaseMethods[] = {
     {"native_setup",            "()V",  (void *)android_mtp_MtpDatabase_setup},
     {"native_finalize",         "()V",  (void *)android_mtp_MtpDatabase_finalize},
 };
 
-static JNINativeMethod gMtpPropertyGroupMethods[] = {
+static const JNINativeMethod gMtpPropertyGroupMethods[] = {
     {"format_date_time",        "(J)Ljava/lang/String;",
                                         (void *)android_mtp_MtpPropertyGroup_format_date_time},
 };