#24 incompatible function pointer types

[Ryan Carsten Schmidt]

xine-lib 1.2.13 fails to build on macOS 14 and 15:

video_out_macosx.m:379:92: error: incompatible function pointer types initializing 'void *(*)(xine_t *, const void *)' (aka 'void *(*)(struct xine_s *, const void *)') with an expression of type 'void *(xine_t *, void *)' (aka 'void *(struct xine_s *, void *)') [-Wincompatible-function-pointer-types]
  { PLUGIN_VIDEO_OUT | PLUGIN_NO_UNLOAD, 22, "macosx", XINE_VERSION_CODE, &vo_info_macosx, init_class },
                                                                                           ^~~~~~~~~~