m4: virt-sanlock: drop check for sanlock_inq_lockspace

m4: virt-sanlock: drop check for sanlock_inq_lockspace

This check was introduced by commit
<96a02703daad4dc6663165adbc0feade9900cebd> to guard calling
sanlock_inq_lockspace() function but it used SANLK_INQ_WAIT as a
parameter which was introduced later.  This was eventually fixed by
commit <238dba0f9c925359cb3b8beddd8c8ae739cb4e06>.

We can safely replace check for sanlock_inq_lockspace as that function
was introduced in sanlock-1.9.  The oldest used version, sanlock-2.2,
is by Ubuntu 16.04.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>