Fix cmplog collection in ASAN builds (#3387)

In `__libafl_targets_cmplog_routines_len` and
`__libafl_targets_cmplog_routines_extended_len`, `area_is_valid` was
called with `CMPLOG_RTN_LEN` as length instead of the length passed as
argument.

In ASAN instrumented builds, this leads to an early exit since ASAN
would detect the region as poisoned anytime the argument's actual length
is less than `CMPLOG_RTN_LEN`.

Fix this issue by passing the len argument instead of `CMPLOG_RTN_LEN`.

Author: alhijazi