axolotl: configs: media: adjust max codec instances for secure decoders

Test: run cts -m CtsMediaCodecTestCases -t android.media.codec.cts.MediaCodecCapabilitiesTest#testGetMaxSupportedInstances

Change-Id: I5e575e9b858a33a32da0ff3a4fe3dcb20fd315ac
Signed-off-by: Alexander Martinz <amartinz@shiftphones.com>