Add linux softirq ids

Add linux softirq ids

The SoftIRQs are pretty much cast in stone on linux. This patch adds the
definition, as they are found in the softirq_entry event and vec field.

Change-Id: If4b3931d777eda540e3f2090939cd59ecd8d1643
Signed-off-by: Francis Giraldeau <francis.giraldeau@gmail.com>
Reviewed-on: https://git.eclipse.org/r/58256
Reviewed-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Tested-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Reviewed-by: Hudson CI