Disconnect from surface when the RenderSurface object is removed.

When a display is created, SurfaceFlinger creates a DisplayDevice object that
handles connecting to the surface. This is done through the RenderSurface
class. However, there's no implicit call to disconnect the surface when the
DisplayDevice is removed, leaving the surface connected. This prevents the
surface from behing able to get connected to to another renderer.

This change adds the disconnect call in the destructor of the RenderSurface
object to ensure it's disconnected when the renderer is removed.

Fixes: 124415123
Test: No longer repro issue in bug
Test: VirtualDisplayTest.VirtualDisplayDestroyedSurfaceReuse
Test: libsurfaceflinger_unittest
Test: libcompositionengine_test
Change-Id: I2061e4e66c63f2b46608f599dcb31304ac8e11f5