Revert "isdn: mISDNinfineon: fix potential NULL pointer dereference"

Revert "isdn: mISDNinfineon: fix potential NULL pointer dereference"

BugLink: https://bugs.launchpad.net/bugs/1931896
[ Upstream commit abd7bca23bd4247124265152d00ffd4b2b0d6877 ]

This reverts commit d721fe99f6ada070ae8fc0ec3e01ce5a42def0d9.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be incorrect for the reasons
below, so it must be reverted.  It will be fixed up "correctly" in a
later kernel change.

The original commit was incorrect, it should have never have used
"unlikely()" and if it ever does trigger, resources are left grabbed.

Given there are no users for this code around, I'll just revert this and
leave it "as is" as the odds that ioremap() will ever fail here is
horrendiously low.

Cc: Kangjie Lu <kjlu@umn.edu>
Cc: David S. Miller <davem@davemloft.net>
Link: https://lore.kernel.org/r/20210503115736.2104747-41-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>