prima: Fix memleak in sap_auth_offload_update_rsn_ie

In the function sap_auth_offload_update_rsn_ie, pdot11f_rsn is
allocated and copied to pdot11f. But it is not freed after copy.
This results in memory leak in  sap_auth_offload_update_rsn_ie.

Free the memory allocated for pdot11f_rsn before exit.

Change-Id: Iba9221fd4688d4a9adbdd5a0fa5b114202335738
CRs-Fixed: 2315529