trace: Relax trace-events parsing regex in simpletrace.py
The regular expression to parse trace event definitions assumed the
format string would be a simple double-quoted string. However, we now
use PRI?64 for portability which splits string literals. The regular
expression can disregard the format string entirely since simpletrace.py
never needs to use it.
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>