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/ospfd/ospf_lsa.c b/ospfd/ospf_lsa.c
index a2d400f..fa36a02 100644
--- a/ospfd/ospf_lsa.c
+++ b/ospfd/ospf_lsa.c
@@ -746,7 +746,7 @@
   return 0;
 }
 
-inline static void
+static void
 ospf_stub_router_check (struct ospf_area *area)
 {
   /* area must either be administratively configured to be stub