Fix unused variable warning on METAL (see bug #5430)
diff --git a/src/render/metal/SDL_render_metal.m b/src/render/metal/SDL_render_metal.m
index ea7a693..fcb8286 100644
--- a/src/render/metal/SDL_render_metal.m
+++ b/src/render/metal/SDL_render_metal.m
@@ -842,8 +842,6 @@ METAL_UpdateTextureNV(SDL_Renderer * renderer, SDL_Texture * texture,
const Uint8 *UVplane, int UVpitch)
{ @autoreleasepool {
METAL_TextureData *texturedata = (__bridge METAL_TextureData *)texture->driverdata;
- const int Uslice = 0;
- const int Vslice = 1;
SDL_Rect UVrect = {rect->x / 2, rect->y / 2, (rect->w + 1) / 2, (rect->h + 1) / 2};
/* Bail out if we're supposed to update an empty rectangle */