dt/bindings: exynos-rng: Move dt binding documentation to bindings/crypto

Samsung exynos PRNG driver is using crypto framework instead of
hw_random framework. So move the devicetree binding to crypto folder.
Signed-off-by: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

MAINTAINERS

@@ -11743,7 +11743,7 @@ L:	linux-crypto@vger.kernel.org
 L:	linux-samsung-soc@vger.kernel.org
 S:	Maintained
 F:	drivers/crypto/exynos-rng.c
-F:	Documentation/devicetree/bindings/rng/samsung,exynos-rng4.txt
+F:	Documentation/devicetree/bindings/crypto/samsung,exynos-rng4.txt
 
 SAMSUNG FRAMEBUFFER DRIVER
 M:	Jingoo Han <jingoohan1@gmail.com>