Make shadow_logfd and Prog not extern

Closes #444
Closes #465

Signed-off-by: Serge Hallyn <serge@hallyn.com>

lib/prototypes.h

@@ -59,9 +59,6 @@
 #include "defines.h"
 #include "commonio.h"
 
-extern /*@observer@*/ const char *Prog; /* Program name showed in error messages */
-extern FILE *shadow_logfd;  /* file descripter to which error messages are printed */
-
 /* addgrps.c */
 #if defined (HAVE_SETGROUPS) && ! defined (USE_PAM)
 extern int add_groups (const char *);