tracing: segger-sysview: fix display formatting

Fixes several minor display errors in the Segger SystemView output:
* Off-by-one error in some trace ids.
* Add missing syscall trace id.
* Displays easier to read syscall function names.
* Fixes syntax error in k_timer_start output.

Signed-off-by: Florian Grandel <fgrandel@code-for-humans.de>