arm/dt: msm8974: add support for DragonBoard APQ8074

DragonBoard is a QCOM development platform assembled in
a SOM Q7 form factor, featuring a Mini-ITX compliant Carrier board.
SOM chip-set: APQ8074, PMIC8941, PMIC8841, QCA6234 and WGR7640.
Carrier board includes a WCD9320 Codec, USB hubs and other peripherals.

Change-Id: I93814deb88e66331329626d7ba481a07089c1ad1
Signed-off-by: Eugene Yasman <eyasman@codeaurora.org>
Signed-off-by: Asaf Penso <apenso@codeaurora.org>
Signed-off-by: Tanya Finkel <tfinkel@codeaurora.org>
Signed-off-by: Ilia Lin <ilialin@codeaurora.org>