ipacm: fix the err_type override issue

Without ipacm-diag debug component, all
the debug prints will have NOFILE err_type
and overrides the kernel error codes. The fix
is to cache it onve we got error from
kernel.

Bug: 109872530
Change-Id: I222f0eceaff1c2f8e5d5c71556a3a1df0c053eaa