Standardise header includes

Changes "SDL_*.h" and "SDL3/SDL_*.h" to <SDL3/SDL_*.h>

include/SDL3/SDL_camera.h

@@ -28,7 +28,7 @@
 #ifndef SDL_camera_h_
 #define SDL_camera_h_
 
-#include "SDL3/SDL_video.h"
+#include <SDL3/SDL_video.h>
 
 #include <SDL3/SDL_begin_code.h>
 /* Set up for C function definitions, even when using C++ */

include/SDL3/SDL_egl.h

@@ -25,7 +25,7 @@
  *  This is a simple file to encapsulate the EGL API headers.
  */
 
-#include "SDL_platform_defines.h"
+#include <SDL3/SDL_platform_defines.h>
 
 #if !defined(_MSC_VER) && !defined(SDL_PLATFORM_ANDROID) && !defined(SDL_USE_BUILTIN_OPENGL_DEFINITIONS)
 

include/SDL3/SDL_pen.h

@@ -45,9 +45,9 @@
 #ifndef SDL_pen_h_
 #define SDL_pen_h_
 
-#include "SDL_error.h"
-#include "SDL_guid.h"
-#include "SDL_stdinc.h"
+#include <SDL3/SDL_error.h>
+#include <SDL3/SDL_guid.h>
+#include <SDL3/SDL_stdinc.h>
 
 /* Set up for C function definitions, even when using C++ */
 #ifdef __cplusplus