ARM: dts: tq imx7 common board support

This adds TQMa7 and MBa7 board support.
TQMa7 can be mounted with either i.MX7 Solo or Dual.
All TQMa7 board variants can be mounted in MBa7 carrier board.

Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>