Fuzzing: Expose `DONT_FAIL_ON_CRC_ERROR` as a CMake option and honor it in the rar5...

Fuzzing: Expose `DONT_FAIL_ON_CRC_ERROR` as a CMake option and honor it in the rar5 decoder (#2229)

Hey,

the fuzzing infrastructure over at OSSFuzz builds libarchive with the
CMake option `-DDONT_FAIL_ON_CRC_ERROR=1`.

https://github.com/google/oss-fuzz/blob/e4643b64b3af4932bff23bb87afdfbac2a301969/projects/libarchive/build.sh#L35
This, unfortunatly, does not do anything since it's never been defined
as an option.

Building the fuzzers with CRC checks disabled should improve fuzzing
efficacy a bunch.

Thanks!