Fixed bug 2187 - CMake is not adding src/core/linux/*.c to the build, linking to SDL results in errors.

Daniel Ribeiro Maciel

CMake is not adding src/core/linux/*.c to the build, linking to SDL results in errors:

(...)/libSDL2-2.0.so.1.0.1: undefined reference to `SDL_UDEV_AddCallback'
(...)/libSDL2-2.0.so.1.0.1: undefined reference to `SDL_UDEV_Poll'
(...)/libSDL2-2.0.so.1.0.1: undefined reference to `SDL_UDEV_Init'
(...)/libSDL2-2.0.so.1.0.1: undefined reference to `SDL_UDEV_Quit'
(...)/libSDL2-2.0.so.1.0.1: undefined reference to `SDL_UDEV_DelCallback'
(...)/libSDL2-2.0.so.1.0.1: undefined reference to `SDL_UDEV_Scan'
collect2: error: ld returned 1 exit status