[pan: 7/21] Fix two compile errors when build with GMime3

[Dominique Dumont <ddumont src gnome org>]

commit 3b35d8b00702f4a0d57e5ce6a95750d8c0dddb16
Author: Detlef Graef <detlef graef gmx de>
Date:   Mon Jun 14 17:24:19 2021 +0200

    Fix two compile errors when build with GMime3

 pan/usenet-utils/mime-utils.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/pan/usenet-utils/mime-utils.cc b/pan/usenet-utils/mime-utils.cc
index 881df7b..1a3f95f 100644
--- a/pan/usenet-utils/mime-utils.cc
+++ b/pan/usenet-utils/mime-utils.cc
@@ -1749,7 +1749,7 @@ namespace pan
 #ifdef HAVE_GMIME_30
     GMimeObject *gmo;
     gmo = g_mime_message_get_mime_part (body);
-    if (g_mime_multipart_signed_sign (gpg_ctx, gmo, uid.c_str(), &err) <0)
+    if (g_mime_multipart_signed_sign (gpg_ctx, gmo, uid.c_str(), &err) != NULL)
 #else
     if (g_mime_multipart_signed_sign (mps, GMIME_OBJECT (part), gpg_ctx, uid.c_str(), 
GMIME_DIGEST_ALGO_SHA1, &err) <0)
 #endif
@@ -1784,7 +1784,7 @@ namespace pan
 
 #ifdef HAVE_GMIME_30
     if (g_mime_multipart_encrypted_encrypt(gpg_ctx, GMIME_OBJECT (part), sign, uid.c_str(),
-                                           GMIME_ENCRYPT_NONE, rcp, &err) < 0)
+                                           GMIME_ENCRYPT_NONE, rcp, &err) != NULL)
 #else
     if (g_mime_multipart_encrypted_encrypt(mpe, GMIME_OBJECT (part), gpg_ctx, sign,
                                            uid.c_str(), GMIME_DIGEST_ALGO_SHA1, rcp, &err) < 0)