ARM: pxa/cm-x300: fix V3020 RTC functionality

While in sleep mode the CS# and other V3020 RTC GPIOs must be driven
high, otherwise V3020 RTC fails to keep the right time in sleep mode.

Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
Cc: stable@kernel.org
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>