unify code path for adding PKCS#11 providers

Use existing wrapper for pkcs11h_addProvider to have arguments with
"magic values" for pkcs11-helper call in a central place.

Slot event argument to pkcs11h_addProvider has NOT been a boolean for
at least 15 years.
Luckily the default is PKCS11H_SLOTEVENT_METHOD_AUTO=0=FALSE.

Signed-off-by: Marc Becker <marc.becker@astos.de>
Acked-by: Frank Lichtenheld <frank@lichtenheld.com>
Message-Id: <20221211190913.190-1-marc.becker@astos.de>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg25642.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>
(cherry picked from commit 8958a36)

Author: astos-marcb

src/openvpn/pkcs11.c

@@ -853,19 +853,9 @@ show_pkcs11_ids(
         goto cleanup;
     }
 
-    if (
-        (rv = pkcs11h_addProvider(
-             provider,
-             provider,
-             TRUE,
-             0,
-             FALSE,
-             0,
-             cert_private ? TRUE : FALSE
-             )) != CKR_OK
-        )
+    if (!pkcs11_addProvider(provider, TRUE, 0, cert_private ? TRUE : FALSE))
     {
-        msg(M_FATAL, "PKCS#11: Cannot add provider '%s' %ld-'%s'", provider, rv, pkcs11h_getMessage(rv));
+        msg(M_FATAL, "Failed to add PKCS#11 provider '%s", provider);
         goto cleanup;
     }