FROMLIST: binder: remove unneeded cleanup code

(from https://patchwork.kernel.org/patch/9817817/

)

The buffer's transaction has already been freed before
binder_deferred_release. No need to do it again.

Change-Id: I2451a22aee72796d7ca1fc6c1406e22a706200c5
Signed-off-by: Todd Kjos <tkjos@google.com>