need to report the line number.  otherwise it's a goose chase.

Reference: /n/atom/patch/applied2013/jukefsnit
Date: Mon Aug 12 06:18:58 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/games/music/jukefs/parse.c	Mon Aug 12 06:18:39 2013
+++ /sys/src/games/music/jukefs/parse.c	Mon Aug 12 06:18:40 2013
@@ -118,7 +118,7 @@
 	}
 	assert(strlen(token) < MAXTOKEN);
 	if(strchr(p, '{'))
-		sysfatal("Illegal keyword or parse error: %s", p);
+		sysfatal("%s:%d: illegal keyword or parse error: %s", file, str, p);
 	if((q = strchr(p, '='))){
 		if(q == p) goto tx;
 		*q = 0;