interconnect: Relax requirement in of_icc_get_from_provider()

This patch relaxes the condition in of_icc_get_from_provider() so that
it is no longer required to set '#interconnect-cells' to <1> in the DT,
and therefore it is not required to supply dummy node IDs in the
'interconnects' property when node IDs are dynamically generated rather
than hardcoded (statically allocated).

In case of the devfreq driver for exynos-bus, node IDs are dynamically
allocated and '#interconnect-cells' is always zero.

Signed-off-by: Artur Świgoń <a.swigon@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Link: https://lore.kernel.org/r/20200521122841.8867-3-s.nawrocki@samsung.com
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>

drivers/interconnect/core.c

@@ -339,7 +339,7 @@ struct icc_node *of_icc_get_from_provider(struct of_phandle_args *spec)
 	struct icc_node *node = ERR_PTR(-EPROBE_DEFER);
 	struct icc_provider *provider;
 
-	if (!spec || spec->args_count != 1)
+	if (!spec)
 		return ERR_PTR(-EINVAL);
 
 	mutex_lock(&icc_lock);