soc: qcom: hyp_core_ctl: Catch uninitialized freq QOS object

Currently, the code is not checking if the freq qos object was
requested before using it in the undo reservation path.
This causes warnings like "freq_qos_update_request() called for
unknown object".
Fix this by checking freq_qos_init_done flag is set prior to using the
qos objects.

Change-Id: Ie8009f5ea191f4ad0c199a3fce04376871a5d2c5
Signed-off-by: Sai Harshini Nimmala <snimmala@codeaurora.org>