ARM: 7494/1: use generic termios.h

As pointed out by Arnd Bergmann, this fixes a couple of issues but will
increase code size:

The original macro user_termio_to_kernel_termios was not endian safe. It
used an unsigned short ptr to access the low bits in a 32-bit word.

Both user_termio_to_kernel_termios and kernel_termios_to_user_termio are
missing error checking on put_user/get_user and copy_to/from_user.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/include/asm/Kbuild

@@ -31,6 +31,7 @@ generic-y += sizes.h
 generic-y += socket.h
 generic-y += sockios.h
 generic-y += termbits.h
+generic-y += termios.h
 generic-y += timex.h
 generic-y += types.h
 generic-y += unaligned.h