ARM: dts: qcom: Adjust memory-hotplug region size for kona

Increase the minimum size of the Normal zone to 5600 Mb.
The current largest expected memory usecase is approximately:
Managed:         5700 Mb
CMA:	          300 Mb
Ion:             3400 Mb
Slab:		  700 Mb
Misc GFP_KERNEL:  800 Mb
Anon/File LRU:    300 Mb
Vmalloc:          100 Mb
Spare:            100 Mb

Movable Zone:
Managed:         2000 Mb
Anon/File LRU:   1000 Mb
Spare:           1000 Mb.

Change-Id: I65835ff29f1022daf86df39fd6d743e34ef2f152