msm:ipa: Fix memleak issue

While initializing IPv6 NAT device, temp memory has been allocated,
but it has not been used. Initialize device temp memory with the
allocated temp memory which will be used in deletion.

Change-Id: Ib6f6457231a3737eea8556ef92099516396a5fe1
Acked-by: Pooja Kumari <kumarip@qti.qualcomm.com>
Signed-off-by: Mohammed Javid <mjavid@codeaurora.org>