- Rename getpty() to xgetpty() and adjust callers.

- Rewrite kbd_mode and setconsole
- Introduce and use console_make_active() and xopen_xwrite_close()
- honour buffer-reservation method as set by the user (dumpkmap, loadkmap)
- shrink rtcwake and some console-tools

  Saves about 270 Bytes

scripts/defconfig

@@ -516,7 +516,7 @@ CONFIG_FEATURE_MOUNT_FSTAB=y
 CONFIG_PIVOT_ROOT=y
 CONFIG_RDATE=y
 CONFIG_READPROFILE=y
-# CONFIG_RTCWAKE is not set
+CONFIG_RTCWAKE=y
 CONFIG_SETARCH=y
 CONFIG_SWAPONOFF=y
 CONFIG_SWITCH_ROOT=y
@@ -534,10 +534,10 @@ CONFIG_FEATURE_MOUNT_LOOP=y
 #
 CONFIG_ADJTIMEX=y
 # CONFIG_BBCONFIG is not set
-# CONFIG_CHAT is not set
-# CONFIG_FEATURE_CHAT_NOFAIL is not set
+CONFIG_CHAT=y
+CONFIG_FEATURE_CHAT_NOFAIL=y
 # CONFIG_FEATURE_CHAT_TTY_HIFI is not set
-# CONFIG_FEATURE_CHAT_IMPLICIT_CR is not set
+CONFIG_FEATURE_CHAT_IMPLICIT_CR=y
 # CONFIG_FEATURE_CHAT_SWALLOW_OPTS is not set
 # CONFIG_FEATURE_CHAT_SEND_ESCAPES is not set
 # CONFIG_FEATURE_CHAT_VAR_ABORT_LEN is not set