ARM: dts: msm: add restart node for reboot support

Add the restart device node for MSM8610, MSM8226, MSM8974
APQ8084, MPQ8092, FSM9900 and MDM9630 used by the
msm power off driver to drop ps hold and reset the chip.

Change-Id: I979df189e8fd1b729e6bb364c2a7f7600d6dc158
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>