usb: qusb: Keep regulators on in probe if EUD is enabled

EUD may be enabled in boot loader and to keep EUD session
alive across kernel boot till USB phy driver is initialized
based on cable status, keep regulators on from USB high speed
phy driver's probe. Regulators shall get turn off while
handling USB cable disconnect routine for both boot up with
and without USB cable case.

Change-Id: I7ebdc0237d7db3e45b61a57264a5564bfa01ed1c
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>