sunxi: H616: add LPDDR3 DRAM support

The H616 SoC has support for several types of DRAM: DDR3, LPDDR3,
DDR4 and LPDDR4.
At the moment, the driver only supports DDR3 memory.
Let's extend the driver to support the LPDDR3 memory. All "magic"
values obtained from the boot0.

Signed-off-by: Mikhail Kalashnikov <iuncuim@gmail.com>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>