uml got broken by commit 30742d5c

... if you revert a commit, revert the fixups elsewhere that had been
triggered by it.  Such as 8c56250f
(lockdep, UML: fix compilation when CONFIG_TRACE_IRQFLAGS_SUPPORT is not set).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>