USB: Fix QUSB PHY initialization sequence

It is suggested to turn OFF QUSB PHY's ref_clk before performing QUSB
PHY reset, wait for 150us after QUSB PHY initialization and turn ON
ref_clk back. Also check QUSB PHY PLL status after QUSB PHY
initialization to confirm that initialization is successful. This
change also adds support to get QUSB PHY ref_clk related BCR address
and use the same for turning OFF before performing QUSB PHY reset.

Change-Id: I1afea226cac5537cd3000d520e773380dbd86de1
Signed-off-by: Mayank Rana <mrana@codeaurora.org>