fix: If any signature is valid, the file is properly signed (#1936)

Author: aliyunav

libyara/modules/pe/pe.c

@@ -1757,7 +1757,7 @@ void _process_authenticode(
   {
     const Authenticode* authenticode = auth_array->signatures[i];
 
-    signature_valid = authenticode->verify_flags == AUTHENTICODE_VFY_VALID
+    signature_valid |= authenticode->verify_flags == AUTHENTICODE_VFY_VALID
                           ? true
                           : false;