Revert "opp: Expose of-node's name in debugfs"

This reverts commit 7295544b.

It breaks the kernel abi so revert it for now.  We will add it back
later at the next kabi update.

Bug: 161946584
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Ie774460786d95e29867a16f3b126463153ee4a7a