Fix get_kprobe_functions

get_kprobe_functions will not only return a function that matches the
regular expression, but also any function that starts with a
substrings that matches it. This is obviously not the intended
behavior.
The issue is easily fixed by replacing re.match by re.fullmatch.

src/python/bcc/__init__.py

@@ -748,7 +748,7 @@ def get_kprobe_functions(event_re):
  # Exclude all gcc 8's extra .cold functions
  elif re.match(b'^.*\.cold(\.\d+)?$', fn):
  continue
- if (t.lower() in [b't', b'w']) and re.match(event_re, fn) \
+ if (t.lower() in [b't', b'w']) and re.fullmatch(event_re, fn) \
  and fn not in blacklist:
  fns.append(fn)
  return set(fns) # Some functions may appear more than once