tty: remove redundant 'default n' from Kconfig-s

'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.

Also since commit f467c5640c29 ("kconfig: only write '# CONFIG_FOO
is not set' for visible symbols") the Kconfig behavior is the same
regardless of 'default n' being present or not:

...
One side effect of (and the main motivation for) this change is making
the following two definitions behave exactly the same:

config FOO
bool

config FOO
bool
default n

With this change, neither of these will generate a
'# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
That might make it clearer to people that a bare 'default n' is
redundant.
...

Signed-off-by: Bartlomiej Zolnierkiewicz <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/tty/Kconfig

···
 config VT_HW_CONSOLE_BINDING
        bool "Support for binding and unbinding console drivers"
        depends on HW_CONSOLE
-       default n
        ---help---
          The virtual terminal is the device that interacts with the physical
          terminal through console drivers. On these systems, at least one
···
 config TRACE_ROUTER
 	tristate "Trace data router for MIPI P1149.7 cJTAG standard"
 	depends on TRACE_SINK
-	default n
 	help
 	  The trace router uses the Linux tty line discipline framework to
 	  route trace data coming from a tty port (say UART for example) to
···
 
 config TRACE_SINK
 	tristate "Trace data sink for MIPI P1149.7 cJTAG standard"
-	default n
 	help
 	  The trace sink uses the Linux line discipline framework to receive
 	  trace data coming from the trace router line discipline driver

drivers/tty/hvc/Kconfig

···
 config HVC_OLD_HVSI
 	bool "Old driver for pSeries serial port (/dev/hvsi*)"
 	depends on HVC_CONSOLE
-	default n
 
 config HVC_OPAL
 	bool "OPAL Console support"
···
        bool "udbg based fake hypervisor console"
        depends on PPC
        select HVC_DRIVER
-       default n
        help
          This is meant to be used during HW bring up or debugging when
 	 no other console mechanism exist but udbg, to get you a quick

drivers/tty/serial/Kconfig

···
 	depends on SPI_MASTER
 	select SERIAL_CORE
 	select REGMAP_SPI if SPI_MASTER
-	default n
 	help
 	  This selects support for an advanced UART from Maxim (Dallas).
 	  Supported ICs are MAX3107, MAX3108, MAX3109, MAX14830.
···
 config PDC_CONSOLE
 	bool "PDC software console support"
 	depends on PARISC && !SERIAL_MUX && VT
-	default n
 	help
 	  Saying Y here will enable the software based PDC console to be 
 	  used as the system console.  This is useful for machines in 
···
 	depends on QUICC_ENGINE
 	select SERIAL_CORE
 	select FW_LOADER
-	default n
 	help
 	  This driver supports the QE serial ports on Freescale embedded
 	  PowerPC that contain a QUICC Engine.