The decklink driver eventually crashes after repeated creation/deletion
of device, input, output, and configuration objects. Change to create
these at the outset and keep them around forever.
Renames the subdevice property to just device, and has it
return the number of devices in the system in response to
a probe. This is useful both for using multiple capture
cards, and for detecting whether it's worth adding the
element to a pipeline.
Also cleans up the property descriptions.
Builds with MSVC, not tested in MinGW or anything else. Added
COM handling code, borrowed from dshowvideosink. Moved Linux
specific files to ./linux and added Windows specific files to
./win (generated from IDL files in VS9). Added macros to handle
BSTR and defined bool as BOOL. Fixes#655362.
Signed-off-by: David Schleef <ds@schleef.org>