util: auth: use VIR_AUTOPTR for aggregate types

By making use of GNU C's cleanup attribute handled by the
VIR_AUTOPTR macro for declaring aggregate pointer variables,
majority of the calls to *Free functions can be dropped, which
in turn leads to getting rid of most of our cleanup sections.
Signed-off-by: NSukrit Bhatnagar <skrtbhtngr@gmail.com>
Reviewed-by: NErik Skultety <eskultet@redhat.com>

src/util/virauth.c

@@ -111,8 +111,7 @@ virAuthGetCredential(const char *servicename,
                      const char *path,
                      char **value)
 {
-    int ret = -1;
-    virAuthConfigPtr config = NULL;
+    VIR_AUTOPTR(virAuthConfig) config = NULL;
     const char *tmp;
 
     *value = NULL;
@@ -121,23 +120,19 @@ virAuthGetCredential(const char *servicename,
         return 0;
 
     if (!(config = virAuthConfigNew(path)))
-        goto cleanup;
+        return -1;
 
     if (virAuthConfigLookup(config,
                             servicename,
                             hostname,
                             credname,
                             &tmp) < 0)
-        goto cleanup;
+        return -1;
 
     if (VIR_STRDUP(*value, tmp) < 0)
-        goto cleanup;
-
-    ret = 0;
+        return -1;
 
- cleanup:
-    virAuthConfigFree(config);
-    return ret;
+    return 0;
 }