Fixed bug 1949 - Pulseaudio 32 bit audio formats support

Matt Scheirer

Pulse has supported (since version 0.8, at least) 32 bit audio formats that are now becoming available in SDL2. This patch adds those format conversions to the switch clause in the pulseaudio backend.
Fixed compile
Catch out of memory errors creating a window
Added src/thread/pthread/SDL_systls.c to the CMake scripts.

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extra : rebase_source : 53362426e55c8271f8ea19d2e74997d1f01ea52b