busdma - Remove filter functionality

- Remove filtfunc and filtarg arguments from bus_dma_tag_create() and
fix all callers. All callers use NULL today for both filterfunc and
filterarg with one

busdma - Remove filter functionality

- Remove filtfunc and filtarg arguments from bus_dma_tag_create() and
fix all callers. All callers use NULL today for both filterfunc and
filterarg with one exception: if_jme.

- Remove filter functionality internally and parent tag tracking.
Without filter functions, we do not need to keep track of tag
ancestry. All inheritance of the parent tag's parameters occurs when
creating the new child tag.

- rename run_filter() to addr_needs_bounce().

- FreeBSD keeps the filtfunc and filtarg arguments but requires them to
be NULL.

- Drop filterfunc usage from if_jme.

In case of "JMC260 chip full mask revision 2", which has a hardware bug
when it comes to DMA transfers crossing the 4 GB bounday, the parent
buffer tag already limits DMA memory to 32bit address space. As such it
should be safe to drop the filterfunc. The filterfunc was checking if
the lower 32bits of the physical address used for DMA are all 0. In case
of a 32bit address space, the only address where all lower 32-bits are
all zero is 0 itself and I am here assuming that the physical address 0
is not used for DMA transfers!

Mainly obtained from: FreeBSD (commits 7cb028de, 900907f4, 1228b93b, 3933ff56)

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kernel - Add per-process capability-based restrictions

* This new system allows userland to set capability restrictions which
turns off numerous kernel features and root accesses. These restricti

kernel - Add per-process capability-based restrictions

* This new system allows userland to set capability restrictions which
turns off numerous kernel features and root accesses. These restrictions
are inherited by sub-processes recursively. Once set, restrictions cannot
be removed.

Basic restrictions that mimic an unadorned jail can be enabled without
creating a jail, but generally speaking real security also requires
creating a chrooted filesystem topology, and a jail is still needed
to really segregate processes from each other. If you do so, however,
you can (for example) disable mount/umount and most global root-only
features.

* Add new system calls and a manual page for syscap_get(2) and syscap_set(2)

* Add sys/caps.h

* Add the "setcaps" userland utility and manual page.

* Remove priv.9 and the priv_check infrastructure, replacing it with
a newly designed caps infrastructure.

* The intention is to add path restriction lists and similar features to
improve jailess security in the near future, and to optimize the
priv_check code.

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