usb: qmp: phy: Add support to read phy init sequence from device tree file

Currently QMP phy initialization sequence is hard coded in QMP phy driver
for every revision of phy. This makes the driver cluttered and adds static
global variables to hold offset and value tuples for un-needed phy
revisions. Hence enable driver to read this information from device tree
file. This allows two or more phys with same revision and different init
sequence to work with same phy driver. Also add delay parameter to register
offset, value tuples in order to add recommended delay after register
write.

Change-Id: Iefeb4675690d525d3b98688701e5d1754e616607
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>