This amends 5950df2b74. The VST3 SDK does not recursively search
directories that are bundles IFF the file inside the bundle's
architecture folder matches the bundle's name.
In case there's a file with a different name resides inside the
bundle it is treated as standalone, unbundled plugin.
Since Ardour, PBD::Searchpath always does a recursive search, the
bundled plugins need to be weeded after the fact.
This now follows the VST3 SDK by not just checking the arch name,
but also Contents and bundle.vst3 parent dirnames.
Robin Gareus
4ef6ba0039
