Eevee: Shadow: Add high bitdepth option.

This option is here for reducing the memory usage of shadow maps.

Also lower bitdepth are quicker to process.

release/scripts/startup/bl_ui/properties_render.py

@@ -763,6 +763,7 @@ class RENDER_PT_eevee_shadows(RenderButtonsPanel, Panel):
         col = layout.column()
         col.prop(props, "shadow_method")
         col.prop(props, "shadow_size")
+        col.prop(props, "shadow_high_bitdepth")
 
 
 classes = (