tracing: Fix selftest function recursion accounting

The test that checks function recursion does things differently
if the arch does not support all ftrace features. But that really
doesn't make a difference with how the test runs, and either way
the count variable should be 2 at the end.

Currently the test wrongly fails for archs that don't support all
the ftrace features.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>