vision fix

I have no idea whether this prevents the newly discovered impossible().
However, it does fix an obvious typo--in hindsight--that I made 6 years
ago (dealing with temporary lighting for camera flashes).

src/vision.c

@@ -1,4 +1,4 @@
-/* NetHack 3.7	vision.c	$NHDT-Date: 1724939600 2024/08/29 13:53:20 $  $NHDT-Branch: NetHack-3.7 $:$NHDT-Revision: 1.70 $ */
+/* NetHack 3.7	vision.c	$NHDT-Date: 1777205478 2026/04/26 04:11:18 $  $NHDT-Branch: NetHack-3.7 $:$NHDT-Revision: 1.75 $ */
 /* Copyright (c) Dean Luick, with acknowledgements to Dave Cohrs, 1990. */
 /* NetHack may be freely redistributed.  See license for details.       */
 
@@ -58,7 +58,7 @@ const coordxy circle_start[] = {
     /* 4*/ 10,
     /* 5*/ 15,
     /* 6*/ 21,
-    /* 7*/ 38,
+    /* 7*/ 28,
     /* 8*/ 36,
     /* 9*/ 45,
     /*10*/ 55,