error adds its own newline, no need for a second.

Reference: /n/sources/patch/maybe/acid-nits2
Date: Sun Sep  4 17:03:26 CES 2011
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/acid/main.c	Sun Sep  4 17:02:47 2011
+++ /sys/src/cmd/acid/main.c	Sun Sep  4 17:02:46 2011
@@ -172,7 +172,7 @@
 			text = open(aout, OREAD);
 
 		if(text < 0)
-			error("%s: can't open %s: %r\n", argv0, aout);
+			error("%s: can't open %s: %r", argv0, aout);
 		readtext(aout);
 	}
 	if(pid)					/* pid given */
--- /sys/src/cmd/acid/util.c	Sun Sep  4 17:02:50 2011
+++ /sys/src/cmd/acid/util.c	Sun Sep  4 17:02:48 2011
@@ -203,7 +203,7 @@
 		break;
 	}
 	if(ret < 0)
-		error("can't get register %s: %r\n", reg);
+		error("can't get register %s: %r", reg);
 	return v;
 }