K 10
svn:author
V 3
ian
K 8
svn:date
V 27
2017-07-23T21:28:00.744710Z
K 7
svn:log
V 524
Add common code to support realtime clocks that store year without century.

Most realtime clocks store the year as 2 BCD digits.  Some add a century bit
to extend the range another hundred years.  Every clock driver has its own
code to determine the century and pass a full year value to clock_ct_to_ts().
Now clock drivers can just convert BCD to bin and store the result in the
clocktime struct and let the common code figure out the century.  Clocks
with a century bit can just add 100 to year if the century bit is on.

END