K 10
svn:author
V 5
gonzo
K 8
svn:date
V 27
2016-12-16T19:09:57.486356Z
K 7
svn:log
V 212
[spigen] Make "data" part of spigen_transfer optional

Make st_data part of spigen_transfer optional by letting pass zero length
and NULL pointer. SPI controller drivers handle this case fine.

MFC after:	1 week

END