construction of shm cache from the conf pool

[smanolache]

Hello,

I suggest to construct the oidc_cache_cfg_shm_t *context, context->mutex, and context->shm from the s->process->pconf.

Otherwise a new cache (context, mutex, shm) is constructed each time the configuration of the apache server is reloaded. They are freed only when the server is shutdown and the process pool is cleared.

[smanolache]

Thanks for accepting the suggestion.

I think, however, that we could change to pconf in apr_shm_create called from oidc_cache_shm_post_config.

[zandbelt]

ok, see 2e97c4c