ARM: msm: Add support for APQ8074 Dragonboard

This patch adds basic board support for APQ8074 Dragonboard
which belongs to the Snapdragon 800 family.
For now, just support a basic machine with device tree.

Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
Acked-by: Kumar Gala <galak@codeaurora.org>
Signed-off-by: David Brown <davidb@codeaurora.org>
[olof: Split off SoC and board support in separate patches]
Signed-off-by: Olof Johansson <olof@lixom.net>