w1: complete the 1-wire (w1) ds1wm driver search algorithm

w1: complete the 1-wire (w1) ds1wm driver search algorithm

This adds multi-slave support of the w1 bus for the ds1wm Synthesizable
1-Wire Bus Master.  Also many fixes and tweaks based on the rev3 of the
datasheet http://datasheets.maxim-ic.com/en/ds/DS1WM.pdf

Signed-off-by: Jean-François Dagenais <[email protected]>
Cc: Evgeniy Polyakov <[email protected]>
Cc: Szabolcs Gyurko <[email protected]>
Cc: Matt Reimer <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>