Revert "can: fix handling of unmodifiable configuration options fix"

This reverts commit 6f8f768a which was
bce271f2 upstream.

It was applied incorrectly, and isn't needed for 3.14-stable.

Reported-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>