scripts/tracetool: Update maintainer email address

scripts/tracetool: Update maintainer email address

There is an effort in progress to generate a QEMU Python
package. As I'm not sure this old email is still valid,
update it to not produce package with broken maintainer
email.

Patch created mechanically by running:

 $ sed -i 's,\(__email__ *= "\)stefanha@linux.vnet.ibm.com",\1stefanha@redhat.com",' \
         $(git grep -l 'email.*stefanha@linux.vnet.ibm.com')

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20200511082816.696-1-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>