ARM: tegra: usb: check for valid phy clock

ARM: tegra: usb: check for valid phy clock

Check for valid clock after setting up phy
in UTMIP reset

Bug 853708
Bug 886080

(reviewed on http://git-master/r/51555)
(cherry picked from commit 25b340b64ca27971f6d2d555299a749f0394e77e)

Change-Id: I98c79fb1e8961b9af19f3001fe6fbde2b28509a0
Reviewed-on: http://git-master/r/75502
Reviewed-by: Simone Willett <swillett@nvidia.com>
Signed-off-by: Ken Chang <kenc@nvidia.com>
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Reviewed-on: http://git-master/r/76468
Reviewed-by: Automatic_Commit_Validation_User