qcacmn: Fix reachable Assert in convert_target_pdev_id_to_host_pdev_id

Currently, If invalid pdev_id is passed to
convert_target_pdev_id_to_host_pdev_id it results into Assert.

Fix is to remove QDF_ASSERT(0) in convert_target_pdev_id_to_host_pdev_id.
Return WMI_HOST_PDEV_ID_INVALID if convert_target_pdev_id_to_host_pdev_id
receives invalid pdev id.

Change-Id: Icb6a75c3f3664596fbba4532f5b29ed626ba28f2
CRs-Fixed: 2428787