Merge tag 'mxs-soc-3.9' of git://git.linaro.org/people/shawnguo/linux-2.6 into next/soc

From Shawn Guo:
mxs soc changes for 3.9

 - A couple of optimization on timer
 - Some updates on mxs_defconfig

* tag 'mxs-soc-3.9' of git://git.linaro.org/people/shawnguo/linux-2.6:
  ARM: mxs_defconfig: Select CONFIG_DEVTMPFS_MOUNT
  ARM: mxs: decrease mxs_clockevent_device.min_delta_ns to 2 clock cycles
  ARM: mxs: use apbx bus clock to drive the timers on timrotv2
  ARM: mxs: Update mxs_defconfig