Revert "support REP (repeat) escape sequence"

This reverts commit e8392b282c.

There is currently a bug in older ncurses versions (like on OpenBSD) where a
fix for a bug with REP is not backported yet. Most likely in tty/tty_update.c:

Noticed while using lynx (which uses ncurses/curses).
To reproduce using lynx: echo "Z0000000" | lynx -stdin

or using the program:

int
main(void)
{
	WINDOW *win;
	win = initscr();

	printw("Z0000000");

	refresh();

	sleep(5);

	return 0;
}

This prints "ZZZZZZZ" (incorrectly).

st.c

@@ -129,7 +129,6 @@ typedef struct {
 	int charset;  /* current charset */
 	int icharset; /* selected charset for sequence */
 	int *tabs;
-	Rune lastc;   /* last printed char outside of sequence, 0 if control */
 } Term;
 
 /* CSI Escape sequence structs */
@@ -1649,12 +1648,6 @@ csihandle(void)
 		if (csiescseq.arg[0] == 0)
 			ttywrite(vtiden, strlen(vtiden), 0);
 		break;
-	case 'b': /* REP -- if last char is printable print it <n> more times */
-		DEFAULT(csiescseq.arg[0], 1);
-		if (term.lastc)
-			while (csiescseq.arg[0]-- > 0)
-				tputc(term.lastc);
-		break;
 	case 'C': /* CUF -- Cursor <n> Forward */
 	case 'a': /* HPR -- Cursor <n> Forward */
 		DEFAULT(csiescseq.arg[0], 1);
@@ -2380,8 +2373,6 @@ check_control_code:
 		/*
 		 * control codes are not shown ever
 		 */
-		if (!term.esc)
-			term.lastc = 0;
 		return;
 	} else if (term.esc & ESC_START) {
 		if (term.esc & ESC_CSI) {
@@ -2431,7 +2422,6 @@ check_control_code:
 	}
 
 	tsetchar(u, &term.c.attr, term.c.x, term.c.y);
-	term.lastc = u;
 
 	if (width == 2) {
 		gp->mode |= ATTR_WIDE;

st.info

@@ -184,7 +184,6 @@ st-mono| simpleterm monocolor,
 # XTerm extensions
 	rmxx=\E[29m,
 	smxx=\E[9m,
-	rep=%p1%c\E[%p2%{1}%-%db,
 # tmux extensions, see TERMINFO EXTENSIONS in tmux(1)
 	Tc,
 	Ms=\E]52;%p1%s;%p2%s\007,