hs_serialized_database_info() custom allocator but no exposed misc free function

According to the documentation a custom allocator can be used but there is no way to know if a custom allocator is being used.

According to docs:

[hs_error_t](https://intel.github.io/hyperscan/dev-reference/api_files.html#c.hs_error_t) hs_serialized_database_info(const char *bytes, size_t length, char **info)
Utility function providing information about a serialized database.

Parameters
bytes – Pointer to a serialized database.

length – Length in bytes of the serialized database.

info – On success, a string containing the version and platform information for the supplied serialized database is placed in the parameter. The string is allocated using the allocator supplied in [hs_set_misc_allocator()](https://intel.github.io/hyperscan/dev-reference/api_files.html#hs__common_8h_1a28571486e60e29b54d6b5fcf9ec1e0b1) (or malloc() if no allocator was set) and should be freed by the caller.

Returns
[HS_SUCCESS](https://intel.github.io/hyperscan/dev-reference/api_files.html#group__HS__ERROR_1ga2d533509db8628a7e0eb794e2b3e77b0) on success, other values on failure.

The string is allocated using the allocator supplied in `hs_set_misc_allocator()` however `hs_misc_free` is not exposed.

Since `hs_misc_free` is not exposed you have to assume `free()` it would be far better if `hs_misc_free` was exposed to be used to free the memory.

The free free function should be exposed for any custom allocator overrides.