Revert "gpiolib: protect the GPIO device against being dropped while in use by user-space"

This reverts commit 46d8f63b which is
commit bdbbae24 upstream.

It breaks the current Android ABI.  If this is needed on any systems, it
can be brought back in the future in an ABI-safe way.

Bug: 161946584
Change-Id: Id0c09923907ec9e5e926aee9e1545ea7e30e9637
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>