qemu: Fix virDoes*Exist usage

The virGet*ID() functions should be called only if the user exists not when it
doesn't.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

src/qemu/qemu_conf.c

@@ -193,10 +193,10 @@ virQEMUDriverConfigPtr virQEMUDriverConfigNew(bool privileged)
         if (virAsprintf(&cfg->swtpmStorageDir, "%s/lib/libvirt/swtpm",
                         LOCALSTATEDIR) < 0)
             goto error;
-        if (virDoesUserExist("tss") != 0 ||
+        if (!virDoesUserExist("tss") ||
             virGetUserID("tss", &cfg->swtpm_user) < 0)
             cfg->swtpm_user = 0; /* fall back to root */
-        if (virDoesGroupExist("tss") != 0 ||
+        if (!virDoesGroupExist("tss") ||
             virGetGroupID("tss", &cfg->swtpm_group) < 0)
             cfg->swtpm_group = 0; /* fall back to root */
     } else {