LU-8056 libcfs: Support for linux 4.2 kernels

LU-8056 libcfs: Support for linux 4.2 kernels

In kernel version 4.2 commit df6b35f409af0a8ff1ef62f552b8402f3fef8665
header file i387.h was renamed to fpu/api.h

Change-Id: Id4f5f6e73f3c2aeac67b5c87b9c1d310a0a50a50
Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-on: http://review.whamcloud.com/20009
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>