IAudioFlinger: fix incorrect audio patch handle

While updating an exist audio patch, the handle should be pass into
patch panel. Otherwise, patch panel will treat it as a new patch,
then make audio routing incorrect.
Pass handle into patch panel if it exist.

Bug: 194367027
Test: Manual test
Change-Id: I15f0ecd47ec89140cd47f8aabbd9af5bd2b609e8