general: remove inline qualifiers and move in-header functions to objects

* (general) Move functions in headers into files, to be compiled into
  shared object files. Remove inline qualifier from functions. Let the
  compiler do the work.
diff --git a/lib/workqueue.c b/lib/workqueue.c
index 52b5f41..61643bf 100644
--- a/lib/workqueue.c
+++ b/lib/workqueue.c
@@ -103,7 +103,7 @@
   return;
 }
 
-static inline int
+static int
 work_queue_schedule (struct work_queue *wq, unsigned int delay)
 {
   /* if appropriate, schedule work queue thread */