log.h: Avoid unnecessary GNU extension for token pasting

clang says:

  ./log.h:23:18: warning: token pasting of ',' and __VA_ARGS__ is a GNU extension [-Wgnu-zero-variadic-macro-arguments]

We need token pasting here just because of the 'format' in trace():
drop it.

Suggested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

log.h

@@ -17,10 +17,10 @@ void debug(const char *format, ...);
 
 extern int log_trace;
 void trace_init(int enable);
-#define trace(format, ...)						\
+#define trace(...)							\
 	do {								\
 		if (log_trace)						\
-			debug(format, ##__VA_ARGS__);			\
+			debug(__VA_ARGS__);				\
 	} while (0)
 
 void __openlog(const char *ident, int option, int facility);