staging/lustre remove linux/lustre_acl.h

Move the contents of lustre/include/linux/lustre_acl.h to
lustre/include/lustre_acl.h and remove the first header.

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>