x86, vdso: Drop now wrong comment

Now that 1b3f2a72bbcfdf92e368a44448c45eb639b05b5e is in, it is very
important that the below lying comment be removed! :-)

Signed-off-by: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20110718191054.GA18359@liondog.tnic
Acked-by: Andy Lutomirski <luto@mit.edu>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/vdso/vclock_gettime.c

@@ -6,7 +6,6 @@
  *
  * The code should have no internal unresolved relocations.
  * Check with readelf after changing.
- * Also alternative() doesn't work.
  */
 
 /* Disable profiling for userspace code: */