[POWERPC] Enable arbitary speed tty ioctls and split input/output speed

Adding the defines/macros activates the existing code in the tty layer and
allows this platform to use the arbitary speed ioctl setting layer

Signed-off-by: David Woodhouse <[e-mail]>
Cc: Alan Cox <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Paul Mackerras <[e-mail]>

include/asm-powerpc/termbits.h

···
 #define B3000000  00034
 #define B3500000  00035
 #define B4000000  00036
+#define   BOTHER  00037
+
+#define CIBAUD	077600000
+#define IBSHIFT	16		/* Shift from CBAUD to CIBAUD */
 
 #define CSIZE	00001400
 #define   CS5	00000000