ARM: pxa: Update Balloon3 for new FPGA firmware

The new FPGA firmware in Balloon3 uses different methods to control it's bus
control lines. In the new version, there are separate registers to set/clear
bus control lines. This patch updates affected places.

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>