selftests/x86: Fix build bug caused by the 5lvl test which has been moved to the VM directory

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kselftest@vger.kernel.org
Cc: shuah@kernel.org
Fixes: 235266b8

 "selftests/vm: move 128TB mmap boundary test to generic directory"
Link: http://lkml.kernel.org/r/20180211111013.16888-2-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>