hal: Fix memory leak in listen module

String returned from str_parms_to_str for set/get parameter
key-value pair for listen module is not de-allocated. Fix is
to make sure the memory allocated for key value pair
is de-allocated.

CRs-Fixed: 610083
Change-Id: I290e61168b8fd1569a7b89e13257e142aa5aa1ac
1 file changed