rsx: Rework memory protection management for framebuffer access

- Avoid re-locking memory if there is no reason to do so (no draws issued)
- Actively bound regions should always get written to the backing cache
- Forcefully read memory during download if writes to the target have occured since last sync event

rpcs3/Emu/RSX/RSXThread.cpp

@@ -330,6 +330,9 @@ namespace rsx
 
 		in_begin_end = false;
 
+		m_graphics_state |= rsx::pipeline_state::framebuffer_reads_dirty;
+		ROP_sync_timestamp = get_system_time();
+
 		for (u8 index = 0; index < rsx::limits::vertex_count; ++index)
 		{
 			//Disabled, see https://github.com/RPCS3/rpcs3/issues/1932