log.c: New functions to hide access to quiet and silent flags

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

src/log.h

@@ -43,6 +43,9 @@
 void    log_init        (int qit, int dbg);
 void    log_exit        (void);
 
+void    log_silent      (void);
+int     log_is_silent   (void);
+
 void    log_debug       (void);
 int     log_is_debug    (void);