There's no need to mark a function as inline in the function
declaration. In fact, it causes a compilation error:

  CC       xmlgen.lo
In file included from acl_parsing.h:29:0,
                 from xmlgen.h:26,
                 from capability_parsing.c:37:
list_util.h:67:21: error: inline function ‘list_node_prev_node’ declared but never defined [-Werror]
 inline list_node_t *list_node_prev_node(list_node_t *node);
                     ^
list_util.h:66:14: error: inline function ‘list_node_prev’ declared but never defined [-Werror]
 inline void        *list_node_prev(list_node_t *node);
              ^
list_util.h:64:21: error: inline function ‘list_node_next_node’ declared but never defined [-Werror]
 inline list_node_t *list_node_next_node(list_node_t *node);
                     ^
list_util.h:63:14: error: inline function ‘list_node_next’ declared but never defined [-Werror]
 inline void        *list_node_next(list_node_t *node);
              ^
list_util.h:61:21: error: inline function ‘list_last_node’ declared but never defined [-Werror]
 inline list_node_t *list_last_node(list_t *list);
                     ^
list_util.h:60:14: error: inline function ‘list_last’ declared but never defined [-Werror]
 inline void        *list_last(list_t *list);
              ^
list_util.h:58:21: error: inline function ‘list_first_node’ declared but never defined [-Werror]
 inline list_node_t *list_first_node(list_t *list);
                     ^
list_util.h:57:14: error: inline function ‘list_first’ declared but never defined [-Werror]
 inline void        *list_first(list_t *list);
              ^
list_util.h:55:13: error: inline function ‘list_node_data_set’ declared but never defined [-Werror]
 inline void  list_node_data_set(list_node_t *node, void *data);
             ^
list_util.h:54:14: error: inline function ‘list_node_data_get’ declared but never defined [-Werror]
 inline void *list_node_data_get(list_node_t *node);
              ^
list_util.h:52:21: error: inline function ‘list_count’ declared but never defined [-Werror]
 inline unsigned int list_count(list_t *list);
                     ^
cc1: all warnings being treated as errors
Makefile:499: recipe for target 'capability_parsing.lo' failed
make[2]: *** [capability_parsing.lo] Error 1
make[2]: *** Waiting for unfinished jobs....

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>