- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

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

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

Loop reading the RTC registers until the same values are obtained
twice, as advised in the atmel docs.

Submitted by: Ian Lapore

Improve a few comments.

Use the RTC unit to get the time. This works on all known AT91SAM9*
processors, either on reboot or after power down with battery backup.
However, the AT91RM9200 RTC always resets on reboot making it just
about useless at the moment (if we support a low-power mode or an
extended sleep mode, it might become useful).

Submitted by: Ian Lepore

Remove pointless semicolons after label

Tweak the disclaimer section of the license to match COPYRIGHT, for
better or worse. Ok'd by folks that have additional copyrights to the
files in cases where there's joint authorship.

Correct return code (int) for at91_rtc_intr() prototype.

Approved by: cognet

o break newbus api: add a new argument of type driver_filter_t to
bus_setup_intr()

o add an int return code to all fast handlers

o retire INTR_FAST/IH_FAST

For more info: http://docs.freebsd.org/cgi/getmsg.cgi?fetch=465712+0+current/freebsd-current

Reviewed by: many
Approved by: re@

Implement the set_time function. Rather pointless with this RTC, as it
resets when the core resets, but there may be some use for it...

Add RTC support. This may be of dubious value since the RTC is reset
to 1998 every reboot.