viced: Set HWHO_INPROGRESS in CheckHost_r

viced: Set HWHO_INPROGRESS in CheckHost_r

When we are probing a host in CheckHost_r, set the HWHO_INPROGRESS
flag on the host, so other threads know that the host is locked while
we are waiting for a probe response, and the h_threadquota mechanism
can work correctly.

Reviewed-on: http://gerrit.openafs.org/4126
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 64d52938ee26e160a6e2cd64253df096eb5d0c1e)

Change-Id: Ib4767e06affcb8e816cf0e4cdff526a9346c8af2
Reviewed-on: http://gerrit.openafs.org/4128
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>