sunxi: DRAM: add Allwinner H5 support

The DRAM controller in the Allwinner H5 SoC is again very similar to
the one in the H3 and A64.
Based on the existing socid parameter, add support for this controller
by reusing the bulk of the code and only deviating where needed.
These new bits set or cleared here and there have been mostly found by
looking at DRAM register dumps after using the H5 boot0 and comparing
them to what we set in the code. So for now it's mostly unclear what
those bits actually mean - hence the missing names and comments.
Also add the delay line parameters taken from the boot0 and libdram
disassembly.
Register setup differences between H5 and H3 are courtesy of Jens Kuske.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/arch/arm/include/asm/arch-sunxi/cpu.h b/arch/arm/include/asm/arch-sunxi/cpu.h
index 6f96a97..e8e670e 100644
--- a/arch/arm/include/asm/arch-sunxi/cpu.h
+++ b/arch/arm/include/asm/arch-sunxi/cpu.h
@@ -15,5 +15,6 @@
 
 #define SOCID_A64	0x1689
 #define SOCID_H3	0x1680
+#define SOCID_H5	0x1718
 
 #endif /* _SUNXI_CPU_H */