sc16is7xx: fix incorrect register bits macro

In datasheet, Modem Status Register MSR[4-7] reflect the modem pins
CTS/DSR/RI/CD signal state.

Signed-off-by: Wills Wang <wills.wang@live.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed