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 r227701, r227847 and r227849:
Move the device_delete_all_children() function from usb_util.c
to kern/subr_bus.c. Simplify this function so that it no longer
depends on malloc() to execute. Rename device_delete_all_children()
into device_delete_children(). Identify a few other places where
it makes sense to use device_delete_children().

MFC r229086, r228483 and r228640:
Implement better support for USB controller suspend and resume.
Fix some build issues in avr32dci.c

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)

Remove unneeded includes of <sys/linker_set.h>. Other headers that use
it internally contain nested includes.

Reviewed by: bde

Add support for the Samsung S3C2xx0 family of ARM SoCs written by
Andrew Turner. The kernel supports the LN2410SBC evaluation board,
and likely others. These parts (or similar ones) are in some open
hardware designs for phones.

Submitted by: Andrew Turner