LU-12678 lnet: use lnet_accept_magic, not le32_to_cpu.

LU-12678 lnet: use lnet_accept_magic, not le32_to_cpu.

This le32_to_cpu() looks wrong, as the argument is a CPU value, not
le32, and the value is being compared to something that might be
le32.  Previous code used lnet_accept_magic() for tests on 'magic',
so it seems to make sense to use lnet_accept_magic() here too.

Test-Parameters: trivial
Signed-off-by: Mr NeilBrown <neilb@suse.de>
Change-Id: I3f04bb087d4ae3d6785e77072b51132f9440bd32
Reviewed-on: https://review.whamcloud.com/36857
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Serguei Smirnov <ssmirnov@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>