LU-11943 llog: Reset current log on ENOSPC

LU-11943 llog: Reset current log on ENOSPC

The original LU-10527 patch:
"LU-10527 obdclass: don't recycle loghandle upon ENOSPC"
https://review.whamcloud.com/#/c/30897/

Kept the current log on ENOSPC.

This appears to cause llog corruption on failover, and the
other part of the original patch (removing an incorrect
assert) should be sufficient to fix the original issue.

Fixes: 5761b9576d39 ("LU-10527 obdclass: don't recycle loghandle upon ENOSPC")
Signed-off-by: Patrick Farrell <pfarrell@whamcloud.com>
Change-Id: Ie5c0ab77940c1be0ec1f166e4d38080b254bed5c
Reviewed-on: https://review.whamcloud.com/34347
Tested-by: Jenkins
Reviewed-by: Faccini Bruno <bruno.faccini@intel.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>