ARM: dts: exynos: fix incomplete Odroid-XU3/4 thermal-zones definition

ARM: dts: exynos: fix incomplete Odroid-XU3/4 thermal-zones definition

Odroid XU3/4 boards have thermal sensors per 4 pairs of A7+A15
cores but currently there is only one thermal-zone (including
cooling maps) defined (for the first pair of cores - the first
core of the A7 cluster and the first core of A15 cluster) so
i.e. if the task is running on any of A15 cores but the first
one, such core can reach high temperature without any proper
cooling action.

Fix it by adding missing thermal-zones definitions.

Also while at it fix the number of steps in cpufreq cooling for
cpu4 (11 steps for A15 corresponds to 700MHz, for 600MHz 12 steps
should be used).

Signed-off-by: Willy Wolff <willy.mh.wolff@gmail.com>
[b.zolnierkie: rewrote patch subject & description + minor fixups]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>