interconnect: qcom: Fix re-initializing the bcm

Currently, qcom_icc_bcm_init always assumes the bcm is not initialized.
There is a possibility that same bcm can belong to multiple providers
and re-initing the bcm adds the same bcm multiple times to the nodes
which are under the control of the bcm.
Hence add condition to check for bcm inited.

Change-Id: I3961963a6ef1a7b76d7ab708f648146fe1a30c99
Signed-off-by: Veera Vegivada <vvegivad@codeaurora.org>