gl_rasterizer_cache: Invert conditional in LoadGLBuffer()

It's generally easier to follow code using conditionals that operate in
terms of the true case followed by the false case (no chance of
overlooking the exclamation mark).

src/video_core/renderer_opengl/gl_rasterizer_cache.cpp

@@ -456,15 +456,15 @@ void CachedSurface::LoadGLBuffer() {
 
     MICROPROFILE_SCOPE(OpenGL_SurfaceLoad);
 
-    if (!params.is_tiled) {
-        const u8* const texture_src_data_end = texture_src_data + copy_size;
-
-        gl_buffer.assign(texture_src_data, texture_src_data_end);
-    } else {
+    if (params.is_tiled) {
         gl_buffer.resize(copy_size);
 
         morton_to_gl_fns[static_cast<size_t>(params.pixel_format)](
             params.width, params.block_height, params.height, gl_buffer.data(), params.addr);
+    } else {
+        const u8* const texture_src_data_end = texture_src_data + copy_size;
+
+        gl_buffer.assign(texture_src_data, texture_src_data_end);
     }
 
     ConvertFormatAsNeeded_LoadGLBuffer(gl_buffer, params.pixel_format, params.width, params.height);