Revert "reader.cpp: send smkx/rmkx when entering/leaving interactive mode"

This reverts commit a66d44054c due to
https://github.com/fish-shell/fish-shell/issues/2406 - entering keypad
mode causes various terminals to send undocumented and highly variable
escapes for keys not specified in the terminfo specification.

src/reader.cpp

@@ -43,20 +43,6 @@ commence.
 #include <sys/select.h>
 #endif
 
-#if HAVE_NCURSES_H
-#include <ncurses.h>
-#elif HAVE_NCURSES_CURSES_H
-#include <ncurses/curses.h>
-#else
-#include <curses.h>
-#endif
-
-#if HAVE_TERM_H
-#include <term.h>
-#elif HAVE_NCURSES_TERM_H
-#include <ncurses/term.h>
-#endif
-
 #include <signal.h>
 #include <fcntl.h>
 #include <wchar.h>
@@ -3097,13 +3083,6 @@ const wchar_t *reader_readline(int nchars)
 
     exec_prompt();
 
-    /* Send the smkx sequence if defined to enable arrow keys etc.
-     See https://github.com/fish-shell/fish-shell/issues/2139 and
-     http://invisible-island.net/xterm/xterm.faq.html#xterm_arrows
-    */
-
-    tputs(keypad_xmit, 1, &writeb);
-
     reader_super_highlight_me_plenty();
     s_reset(&data->screen, screen_reset_abandon_line);
     reader_repaint();
@@ -4216,13 +4195,6 @@ const wchar_t *reader_readline(int nchars)
             wperror(L"tcsetattr");
         }
 
-        /* Send the rmkx sequence if defined to disable arrow keys etc.
-         See https://github.com/fish-shell/fish-shell/issues/2139 and
-         http://invisible-island.net/xterm/xterm.faq.html#xterm_arrows
-        */
-
-        tputs(keypad_local, 1, &writeb);
-
         set_color(rgb_color_t::reset(), rgb_color_t::reset());
     }