ARM: dts: exynos: Use labels instead of full paths in exynos4210-universal_c210

Extend camera, fimc, mct and sysram nodes by labels, not by full path in
Exynos 4210 Universal C210 board.  This avoids error-prone redefinition
of nodes.

Signed-off-by: Maciej Purski <m.purski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>