tweaks: simplify the counting of characters in a section

The line after the given section is always NULL (or when it is not,
it is intended to be NULL), so always subtract 1 at the end.

src/text.c

@@ -2920,10 +2920,9 @@ void do_wordlinechar_count(void)
 		get_region(&topline, &top_x, &botline, &bot_x);
 
 		if (topline != botline)
-			chars = number_of_characters_in(topline->next, botline);
+			chars = number_of_characters_in(topline->next, botline) + 1;
 
 		chars += mbstrlen(topline->data + top_x) - mbstrlen(botline->data + bot_x);
-		chars += (botline->next == NULL) ? 1 : 0;
 	} else {
 		topline = openfile->filetop;
 		top_x = 0;

src/utils.c

@@ -521,10 +521,6 @@ size_t number_of_characters_in(const linestruct *begin, const linestruct *end)
 	for (line = begin; line != end->next; line = line->next)
 		count += mbstrlen(line->data) + 1;
 
-	/* The last line of a file doesn't have a newline -- otherwise it
-	 * wouldn't be the last line -- so subtract 1 when at EOF. */
-	if (line == NULL)
-		count--;
-
-	return count;
+	/* Do not count the final newline. */
+	return (count - 1);
 }

src/winio.c

@@ -3342,10 +3342,6 @@ void do_cursorpos(bool force)
 
 	openfile->current->data[openfile->current_x] = saved_byte;
 
-	/* When not at EOF, subtract 1 for an overcounted newline. */
-	if (openfile->current != openfile->filebot)
-		sum--;
-
 	/* Display the current cursor position on the status bar. */
 	linepct = 100 * openfile->current->lineno / openfile->filebot->lineno;
 	colpct = 100 * cur_xpt / cur_lenpt;