Removed SDL_bool in favor of plain bool

We require stdbool.h in the build environment, so we might as well use the plain bool type.

If your environment doesn't have stdbool.h, this simple replacement will suffice:
typedef signed char bool;

test/teststreaming.c

@@ -63,7 +63,7 @@ static Uint8 MooseFrames[MOOSEFRAMES_COUNT][MOOSEFRAME_SIZE];
 static SDL_Renderer *renderer;
 static int frame;
 static SDL_Texture *MooseTexture;
-static SDL_bool done = SDL_FALSE;
+static bool done = false;
 static SDLTest_CommonState *state;
 
 static void quit(int rc)
@@ -108,11 +108,11 @@ static void loop(void)
         switch (event.type) {
         case SDL_EVENT_KEY_DOWN:
             if (event.key.key == SDLK_ESCAPE) {
-                done = SDL_TRUE;
+                done = true;
             }
             break;
         case SDL_EVENT_QUIT:
-            done = SDL_TRUE;
+            done = true;
             break;
         default:
             break;