trappy: Split out parsing of trace string into separate function
trappy: Split out parsing of trace string into separate function

In preparation of introducing event callbacks, split out string
parsing into separate function.

Signed-off-by: Joel Fernandes <89f39a38232ac523c7644e47b6ca6563177e40b4@google.com>

joelagnel/trappy,joelagnel/trappy,joelagnel/trappy,joelagnel/trappy