selftests/x86: Style fixes for the 'unwind_vdso' test

Checkpatch is really quite bad for user code like this, but it
caught two legit style issues.

Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/3335040bdd40d2bca4b1a28a3f8b165361c801b7.1444696194.git.luto@kernel.org


Signed-off-by: Ingo Molnar <mingo@kernel.org>