mwifiex: pcie: Fix memory leak in mwifiex_pcie_init_evt_ring

mwifiex: pcie: Fix memory leak in mwifiex_pcie_init_evt_ring

BugLink: https://bugs.launchpad.net/bugs/1859712
[ Upstream commit d10dcb615c8e29d403a24d35f8310a7a53e3050c ]

In mwifiex_pcie_init_evt_ring, a new skb is allocated which should be
released if mwifiex_map_pci_memory() fails. The release for skb and
card->evtbd_ring_vbase is added.

Fixes: 0732484b47b5 ("mwifiex: separate ring initialization and ring creation routines")
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Acked-by: Ganapathi Bhat <gbhat@marvell.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>