pcilib_get_data should expect pcilib_error_t or int as error type

[Matthias Vogelgesang]

For some reason, the usage of error types is not really consistent. The error codes are defined as a pcilib_errot_t (sic!) enum, whereas most functions return int (legal but not good style) and some take a pointer to size_t which is bad for obvious reason.

Please use one type, because I don't want to do wrong type casts to avert compilation errors due to -Werror.

[Suren A. Chilingaryan]

Error is declared int everywhere. enum is used just instead of defines. You don't have it anywhere in API functions. For size_t I guess you are referring to this argument 'size_t *size_or_err'. It is actually mainly parameter to return size. At some point I just used opportunity to report errors on NULL without breaking API. So, basically you to pass a size_t variable there for you expect size back. If something fails you may query for error as well. No type conversion needed just use err = size.