LU-4423 lnet: don't open-code kernel_recvmsg()

LU-4423 lnet: don't open-code kernel_recvmsg()

Upstream commit from Al Viro. b2f42cfeeb0452ca3e004c3014cda99b53554d47

Change-Id: Ide4efaab18268d3a69790231b9efa3b8b3e6f928
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: James Simmons <uja.ornl@gmail.com>
Reviewed-on: http://review.whamcloud.com/10124
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Liang Zhen <liang.zhen@intel.com>
Reviewed-by: Isaac Huang <he.huang@intel.com>