msm_11ad: free old pci state before re-allocating

pci_store_saved_state allocates pci state, hence the old state we
saved needs to be released.

Change-Id: I9c7cf43f375b4581bf9f3950d8a790b754589d81
Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Lior David <liord@codeaurora.org>