x11: Don't include XDestroyImage in the table of exported functions

When linking directly to libX11 as a hard dependency, we assign the
addresses of functions like XDestroyImage to function pointers like
X11_XDestroyImage. However, by default Xutils.h doesn't declare
XDestroyImage as a function: it only provides a macro which looks into
the XImage struct and calls a function pointer directly, similar to
a virtual method.

SDL_x11framebuffer.c was already relying on being able to call the macro
without explicitly linking to libX11, so do the same here.

Fixes: d14cbd7b "Introduce X11 toolkit and make message dialogs use it"
Signed-off-by: Simon McVittie <[email protected]>

src/video/x11/SDL_x11sym.h

@@ -105,7 +105,6 @@ SDL_X11_SYM(Status,XInitThreads,(void))
 SDL_X11_SYM(int,XPeekEvent,(Display* a,XEvent* b))
 SDL_X11_SYM(int,XPending,(Display* a))
 SDL_X11_SYM(XImage*,XGetImage,(Display* a,Drawable b,int c, int d,unsigned int e,unsigned int f,unsigned long g,int h))
-SDL_X11_SYM(void,XDestroyImage,(XImage *a))
 SDL_X11_SYM(int,XPutImage,(Display* a,Drawable b,GC c,XImage* d,int e,int f,int g,int h,unsigned int i,unsigned int j))
 SDL_X11_SYM(int,XQueryKeymap,(Display* a,char b[32]))
 SDL_X11_SYM(Bool,XQueryPointer,(Display* a,Window b,Window* c,Window* d,int* e,int* f,int* g,int* h,unsigned int* i))

src/video/x11/SDL_x11toolkit.c

@@ -981,10 +981,10 @@ static void X11Toolkit_DrawWindow(SDL_ToolkitWindowX11 *data) {
         put_image = X11_XCreateImage(data->display, data->visual, data->vi.depth, ZPixmap, 0, put_surface->pixels, data->window_width, data->window_height, 32, put_surface->pitch);
         X11_XPutImage(data->display, data->window, data->ctx, put_image, 0, 0, 0, 0, data->window_width, data->window_height);
 
-        X11_XDestroyImage(pixmap_image);
+        XDestroyImage(pixmap_image);
         /* Needed because XDestroyImage results in a double-free otherwise */
         put_image->data = NULL;
-        X11_XDestroyImage(put_image);
+        XDestroyImage(put_image);
         SDL_DestroySurface(pixmap_surface);
         SDL_DestroySurface(put_surface);
     }