tty: move drivers/serial/ to drivers/tty/serial/

The serial drivers are really just tty drivers, so move them to
drivers/tty/ to make things a bit neater overall.

This is part of the tty/serial driver movement proceedure as proposed by
Arnd Bergmann and approved by everyone involved a number of months ago.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl>
Cc: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/Makefile

@@ -24,7 +24,7 @@ obj-$(CONFIG_XEN)		+= xen/
 # regulators early, since some subsystems rely on them to initialize
 obj-$(CONFIG_REGULATOR)		+= regulator/
 
-# char/ comes before serial/ etc so that the VT console is the boot-time
+# tty/ comes before char/ so that the VT console is the boot-time
 # default.
 obj-y				+= tty/
 obj-y				+= char/
@@ -38,7 +38,6 @@ obj-$(CONFIG_CONNECTOR)		+= connector/
 obj-$(CONFIG_FB_I810)           += video/i810/
 obj-$(CONFIG_FB_INTEL)          += video/intelfb/
 
-obj-y				+= serial/
 obj-$(CONFIG_PARPORT)		+= parport/
 obj-y				+= base/ block/ misc/ mfd/ nfc/
 obj-$(CONFIG_NUBUS)		+= nubus/

drivers/char/Kconfig

@@ -426,7 +426,7 @@ config SGI_MBCS
          If you have an SGI Altix with an attached SABrick
          say Y or M here, otherwise say N.
 
-source "drivers/serial/Kconfig"
+source "drivers/tty/serial/Kconfig"
 
 config UNIX98_PTYS
 	bool "Unix98 PTY support" if EMBEDDED

drivers/tty/Makefile

@@ -10,3 +10,4 @@ obj-$(CONFIG_R3964)		+= n_r3964.o
 
 obj-y				+= vt/
 obj-$(CONFIG_HVC_DRIVER)	+= hvc/
+obj-y				+= serial/