tty: tty_ldisc: Fix some kernel-doc related misdemeanours

- Functions must follow directly on from their headers
- Demote non-conforming kernel-doc header
- Ensure notes have unique section names
- Provide missing description for 'reinit'

Fixes the following W=1 kernel build warning(s):

drivers/tty/tty_ldisc.c:158: warning: cannot understand function prototype: 'int tty_ldisc_autoload = IS_BUILTIN(CONFIG_LDISC_AUTOLOAD); '
drivers/tty/tty_ldisc.c:199: warning: Function parameter or member 'ld' not described in 'tty_ldisc_put'
drivers/tty/tty_ldisc.c:260: warning: duplicate section name 'Note'
drivers/tty/tty_ldisc.c:717: warning: Function parameter or member 'reinit' not described in 'tty_ldisc_hangup'

Cc: Greg Kroah-Hartman <[e-mail]>
Cc: Jiri Slaby <[e-mail]>
Signed-off-by: Lee Jones <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/tty/tty_ldisc.c

···
 	raw_spin_unlock_irqrestore(&tty_ldiscs_lock, flags);
 }
 
+static int tty_ldisc_autoload = IS_BUILTIN(CONFIG_LDISC_AUTOLOAD);
 /**
  *	tty_ldisc_get		-	take a reference to an ldisc
  *	@tty: tty device
···
  *	Locking:
  *		takes tty_ldiscs_lock to guard against ldisc races
  */
-
-static int tty_ldisc_autoload = IS_BUILTIN(CONFIG_LDISC_AUTOLOAD);
 
 static struct tty_ldisc *tty_ldisc_get(struct tty_struct *tty, int disc)
 {
···
 	return ld;
 }
 
-/**
+/*
  *	tty_ldisc_put		-	release the ldisc
  *
  *	Complement of tty_ldisc_get().
···
  *	Returns: NULL if the tty has been hungup and not re-opened with
  *		 a new file descriptor, otherwise valid ldisc reference
  *
- *	Note: Must not be called from an IRQ/timer context. The caller
+ *	Note 1: Must not be called from an IRQ/timer context. The caller
  *	must also be careful not to hold other locks that will deadlock
  *	against a discipline change, such as an existing ldisc reference
  *	(which we check for)
  *
- *	Note: a file_operations routine (read/poll/write) should use this
+ *	Note 2: a file_operations routine (read/poll/write) should use this
  *	function to wait for any ldisc lifetime events to finish.
  */
 
···
 /**
  *	tty_ldisc_hangup		-	hangup ldisc reset
  *	@tty: tty being hung up
+ *	@reinit: whether to re-initialise the tty
  *
  *	Some tty devices reset their termios when they receive a hangup
  *	event. In that situation we must also switch back to N_TTY properly