Fix fd leak in getAvSharedHandleInfo()

After closing the file descriptor (fd) in user space, the kernel space does not immediately release the buffer.
This is because, as per the hardware binder design, the transport data from the binder will be closed on the next transact(...) call.

Bug:298557415
Test: Stress test the fd leak does not occur
(cherry picked from https://partner-android-review.googlesource.com/q/commit:a4d742c99e5739debeabeb0a557c44cf4b19e802)
Merged-In: Ie1954c1c8742844a694a6de2bff8dd09c9269b3c
Change-Id: Ie1954c1c8742844a694a6de2bff8dd09c9269b3c