test: add coverage for audio output and device functions
access: don't link against Cocoa since this isn't needed
demux: don't link against IOKit and CoreFoundation since this isn't needed
omx: remove no-op

These values are already zeroed a few lines above.
omx: fix memory leak on error
XCB: develop picture free function
XCB/X11: keep SysV segment pointer only

...rather than the whole picture resource structure.
XCB/XVideo: keep only SysV segment base address

...rather than the whole picture resource structure.
androidsurface: fix double free on error
androidsurface: remove useless member
kva: fix double free on error, and remove useless struct member
MSW/Direct3D: retain only picture_sys_t* instead of picture_resource_t
MSW/DirectX: keep only picture_sys_t * instead of picture_resource_t
MSW/WinGDI: remove no-op

free(NULL)
XCB: rework picture allocation, fix a memory leak in case of error
picture: add pf_destroy to picture_resource_t
picture: assert that there is a destroy callback

Pictures without destroy callback are allocated on the stack and never
explicitly released.
XCB: use custom picture destroy callback, simplify
XCB/X11: fix long-standing massive leak on error
XCB/XVideo: fix long-standing massive leak on error