ab8500: remove explicit handling of battery type

ab8500: remove explicit handling of battery type

property, battery-type shall be one of supported technology type
instead blank
- refer: Documentation/devicetree/bindings/power_supply/ab8500/fg.txt
	for the list supported types
- this patch appends to ab8500 bm devs DT binding patch set
	ref: commit-id e0f1abeba5c2d8a2183566717d99294fd1a29c2e
		git://git.infradead.org/battery-2.6.git
- promote ab8500_fg probe to happen before ab8500_btemp probe as
	btemp driver depends on fuelgauge list,
	ref: ab8500_fg_get(...)

Signed-off-by: Rajanikanth H.V <rajanikanth.hv@stericsson.com>