Fix memory leaks in fuzzer modules detected by cppchecker #18081

[Lung-Alexandra]

This PR fixes #18081.

This pull request addresses several memory leak issues detected by cppchecker in the following files:

• fuzzer-json.c (line 39):
  Added a free(data) call to release the allocated memory before returning.

• fuzzer-mbregex.c (line 39):
  Implemented a similar fix by freeing the allocated memory for data when fuzzer_request_startup() fails.

• fuzzer-unserialize.c (line 38):
  Now frees orig_data before returning when an error is detected.

• fuzzer-unserializehash.c (line 43):
  Modified the error path to call free(orig_data) if fuzzer_request_startup() fails.

These changes ensure that memory allocated is properly released if fuzzer_request_startup() fails, preventing memory leaks.

[nielsdos]

This affects lower branches too, please target the lowest supported bugfix branch, i.e. PHP-8.3.

[nielsdos]

It's probably also better to just move the allocation under the request initialization, then you don't even need the call to free.

[TimWolla]

This needs to be properly rebased when changing the target branch.

[Lung-Alexandra]

@TimWolla squashed and rebased over PHP-8.3

[staabm]

tabs vs spaces mixed up in all files

[nielsdos]

Please fix indentation to use tabs

[nielsdos]

Thanks