Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC: r227309 (partial)

Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.

The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.

MFC: r243857 (partial)

Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags in sys/dev.

MFC r226173, r227843, r227848 and r227908:
Use DEVMETHOD_END to mark end of device methods.
Remove superfluous device methods.
Add some missing __FBSBID() macros.

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Fix typo, lost 0 in SYSCTL_ADD_INT usage.

Support of Ralink Ethernet MAC, used in RT3050F/RT3052F and I belive in other Ralink SoCs.

Approved by: adrian (mentor)