Camera: Fix SessionProcessor vendor id initialization

The Camera Extension 'SessionProcessor' will infer the
corresponding metadata vendor id by inspecting the incoming
native metadata map. This must be done before the map is
passed to the extension implementation. This step requires
the transfer of the underlying native metadata in to a
new CharacteristicsMap, any subsequent queries will only
be using empty metadata buffers.

Flag: EXEMPT bugfix
Bug: 437259360
Test: Camera CTS
Change-Id: I2c0a7e9485881b4e2273102003fca7ca888c1bea