ipmi: Add an intializer for ipmi_smi_msg struct

There was a "type" element added to this structure, but some static
values were missed.  The default value will be zero, which is correct,
but create an initializer for the type and initialize the type properly
in the initializer to avoid future issues.

Reported-by: Joe Wiese <jwiese@rackspace.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>