lisa._assets.kmodules.lisa: Add thermal trace

- Temperatures of up to 100 (arbitrary limit) thermal zones are
  traced to ftrace by polling.
- Configuration is via VFS.
- The poll interval can be set to a value between 1 and 5000 ms
  and defaults to 100 ms.
- Thermal zones are set using a comma-separated list of names
  (contents of the file /sys/class/thermal/thermal_zoneX/type)

Signed-off-by: Chris Swinchatt <christopher.swinchatt@arm.com>