Revert "qapitrace: fix an inline string FIXME request"

This reverts commit 0d86efd38a375c526491c679f4d2185ebe51434e, from
issue #244, due to two problems I just noticed:

- strcasestr doesn't exist on Windows, and there seems to be no easy
  replacement.

- ApiTraceCall::contains search the string in the whole call (not just
  the name)