linux-phytec-ti

clk: keystone: sci-clk: add support from parsing clock info from DT

Currently the sci-clk driver queries clock data from the firmware, which
can be pretty slow operation in certain cases. Add an option for the
driver to probe the available clocks from DT also, in this case the
number of clocks probed from firmware gets cut down drastically. To
enable the feature, a new flag ti,scan-clocks-from-dt can be added
under the clock provider node.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Tested-by: Andreas Dannenberg <dannenberg@ti.com>