net: ena: add missing unmap bars on device removal

net: ena: add missing unmap bars on device removal

BugLink: http://bugs.launchpad.net/bugs/1701575
This patch also change the mapping functions to devm_ functions

Fixes: 1738cd3ed342 ("Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: Netanel Belgazal <netanel@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 0857d92f71b6cb75281fde913554b2d5436c394b)
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Brad Figg <brad.figg@canonical.com>