soc: qcom: service-locator: Free PD list after client use

Currently, when a client invokes the service-locator to get
the domain list for a service, a data structure is dynamically
allocated to hold this information, and that is given to the
client for use. However, after the client uses the domain list,
the data structure is not freed, resulting in a memory leak.

Free domain list data structure after client use to fix
memory leak.

Change-Id: I2b87afefbb35c2c296b4267450fa3152e3725ab9
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>