USB: phy: tegra: replace mdelay with usleep_range

USB: phy: tegra: replace mdelay with usleep_range

Avoid busy waiting by using usleep_range().

Change-Id: If11f137d5bc1a67e37e232996cac559b7b154545
Signed-off-by: Suresh Mangipudi <smangipudi@nvidia.com>
Reviewed-on: http://git-master/r/432645
(cherry picked from commit 067e4086801c0805846969b8473999afe7b7dd03)
Reviewed-on: http://git-master/r/434624
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Venkat Moganty <vmoganty@nvidia.com>
Reviewed-by: Laxman Dewangan <ldewangan@nvidia.com>