p11_kit_module_load() hands on the module_path argument to
load_module_from_file_inlock() which accepts relative paths, prepending
P11_MODULE_PATH. Update API documentation accordingly.
https://lists.freedesktop.org/archives/p11-glue/2016-February/000587.html
/**
* p11_kit_module_load:
- * @module_path: full file path of module library
+ * @module_path: relative or full file path of module library
* @flags: flags to use when loading the module
*
* Load an arbitrary PKCS\#11 module from a dynamic library file, and
* initialize it. Normally using the p11_kit_modules_load() function
* is preferred.
*
+ * A full file path or just (path/)filename relative to
+ * P11_MODULE_PATH are accepted.
+ *
* Using this function to load modules allows coordination between multiple
* callers of the same module in a single process. If @flags contains the
* %P11_KIT_MODULE_UNMANAGED flag, then the modules will be not be loaded