Fix editor prediction code garbling input

This applies a patch from OpenSUSE. Source:
https://build.opensuse.org/package/view_file/shells/ksh/ksh93-edpredict.dif

| Tue Jul  5 14:49:03 CEST 2016 - mls@suse.de
|
| - fix editor prediction code garbling input [bnc#964966]
|   new patch: ksh93-edpredict.dif

Unfortunately the bug report is not currently public:
https://bugzilla.opensuse.org/show_bug.cgi?id=964966
but this one seems sensible enough and is in production use,
so I'll take it on faith.

src/cmd/ksh93/edit/edit.c

@@ -621,8 +621,8 @@ void	ed_setup(register Edit_t *ep, int fd, int reedit)
 	ep->hoff = 0;
 #endif /* SHOPT_EDPREDICT */
 #if KSHELL
-	ep->e_stkptr = stakptr(0);
 	ep->e_stkoff = staktell();
+	ep->e_stkptr = stakfreeze(0);
 	if(!(last = shp->prompt))
 		last = "";
 	shp->prompt = 0;

src/cmd/ksh93/edit/emacs.c

@@ -726,10 +726,8 @@ int ed_emacsread(void *context, int fd,char *buff,int scend, int reedit)
 	draw(ep,FINAL);
 	tty_cooked(ERRIO);
 	if(ed->e_nlist)
-	{
 		ed->e_nlist = 0;
-		stakset(ed->e_stkptr,ed->e_stkoff);
-	}
+	stakset(ed->e_stkptr,ed->e_stkoff);
 	if(c == '\n')
 	{
 		out[eol++] = '\n';

src/cmd/ksh93/edit/vi.c

@@ -593,10 +593,8 @@ int ed_viread(void *context, int fd, register char *shbuf, int nchar, int reedit
 	/* to cause the shell to process the line */
 	tty_cooked(ERRIO);
 	if(ed->e_nlist)
-	{
 		ed->e_nlist = 0;
-		stakset(ed->e_stkptr,ed->e_stkoff);
-	}
+	stakset(ed->e_stkptr,ed->e_stkoff);
 	if( vp->addnl )
 	{
 		virtual[++last_virt] = '\n';