tty: rocket: fix comment of ROCKET_SPD_HI

This comment does not reflect the actual code.  It should be 57600,
not 56000.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed