fix format specifier compiler warning

Author: Hans Zandbelt

src/cache/shm.c

@@ -233,7 +233,7 @@ static apr_byte_t oidc_cache_shm_set(request_rec *r, const char *section,
 
 	/* check that the passed in value is valid */
 	if ((value != NULL) && (strlen(value) > (cfg->cache_shm_entry_size_max - sizeof(oidc_cache_shm_entry_t)))) {
-		oidc_error(r, "could not store value since value size is too large (%llu > %lu); consider increasing OIDCCacheShmEntrySizeMax",
+		oidc_error(r, "could not store value since value size is too large (%llu > %u); consider increasing OIDCCacheShmEntrySizeMax",
 				(unsigned long long)strlen(value), (cfg->cache_shm_entry_size_max - sizeof(oidc_cache_shm_entry_t)));
 		return FALSE;
 	}