coccinelle: fix problem with coccinelle 1.0rc21

coccinelle 1.0rc21 has a problem with regular expression handling.
This result in a Fatal Error when test system detects an coding
error.

This patch fixes the problem by using a simple blob inside
semantic patch instead of using a regular expression to define
the function.

It also fixes add an optimization on matching suppressing a
useless <.. ..> construction.

Fixes have been suggested by Julia Lawall.