Really pull in tpm2-tss for EPEL8 builds

It should be checking for %{?rhel} >= 8, not %{?epel}.

Not that it'll build yet because ocserv isn't there for EPEL8 yet
(https://bugzilla.redhat.com/show_bug.cgi?id=1761396)

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

openconnect.spec.in

@@ -22,7 +22,7 @@
 %endif
 
 # Fedora has tss2-sys from F29 onwards, and RHEL from 8 onwards.
-%if 0%{?fedora} >= 29 || 0%{?epel} >= 8
+%if 0%{?fedora} >= 29 || 0%{?rhel} >= 8
 %define use_tss2_esys 1
 %else
 %define use_tss2_esys 0