Remove src and unix VISION_TABLES

Remove all references to the unused vision tables in the main source
and unix build.  Leave makedefs able to generate the vision tables.
makdefs will be cleaned up in a different commit, once all ports
are clear of dependencies.

include/config.h

@@ -457,24 +457,15 @@ typedef unsigned char uchar;
 /* #define STRNCMPI */ /* compiler/library has the strncmpi function */
 
 /*
- * There are various choices for the NetHack vision system.  There is a
- * choice of two algorithms with the same behavior.  Defining VISION_TABLES
- * creates huge (60K) tables at compile time, drastically increasing data
- * size, but runs slightly faster than the alternate algorithm.  (MSDOS in
- * particular cannot tolerate the increase in data size; other systems can
- * flip a coin weighted to local conditions.)
+ * Vision choices.
  *
- * If VISION_TABLES is not defined, things will be faster if you can use
- * MACRO_CPATH.  Some cpps, however, cannot deal with the size of the
- * functions that have been macroized.
+ * Things will be faster if you can use MACRO_CPATH.  Some cpps, however,
+ * cannot deal with the size of the functions that have been macroized.
  */
 
-/* #define VISION_TABLES */ /* use vision tables generated at compile time */
-#ifndef VISION_TABLES
 #ifndef NO_MACRO_CPATH
 #define MACRO_CPATH /* use clear_path macros instead of functions */
 #endif
-#endif
 
 #if !defined(MAC)
 #if !defined(NOCLIPPING)

include/extern.h

@@ -2852,12 +2852,6 @@ E int FDECL(assign_videoshades, (char *));
 E int FDECL(assign_videocolors, (char *));
 #endif
 
-/* ### vis_tab.c ### */
-
-#ifdef VISION_TABLES
-E void NDECL(vis_tab_init);
-#endif
-
 /* ### vision.c ### */
 
 E void NDECL(vision_init);