cpufreq: dt: Print error on failing to mark OPPs as shared

We need to explicitly mark OPPs as shared, when they are not defined
with OPP-v2 bindings. This operation can potentially fail, and in that
case we should at least print an error message.

Fixes: 2e02d8723edf ("cpufreq: dt: Add support for operating-points-v2 bindings")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit 8bc862843901e282e58f5ecd66f1df24366ecb6b)
Signed-off-by: Alex Shi <alex.shi@linaro.org>