fix bsearch tables that must be sorted, add comment to all tables that must be sorted

src/common/filetype.c

@@ -48,6 +48,7 @@
 
 
 
+/* CAUTION: table must be sorted for bsearch */
 static const FileId TypeTable[] = {
     /* Upper case stuff for obsolete operating systems */
     {   "A",    FILETYPE_LIB    },

src/common/target.c

@@ -138,8 +138,9 @@ struct TargetEntry {
     target_t    Id;                     /* Target ID */
 };
 
-/* Table that maps target names to IDs. Sorted alphabetically for bsearch().
+/* Table that maps target names to IDs.
 ** Allows multiple entries for one target ID (target name aliases).
+** CAUTION: must be alphabetically for bsearch().
 */
 static const TargetEntry TargetMap[] = {
     {   "apple2",       TGT_APPLE2       },