usb: phy: remove dead code

Commit [4d175f34: usb: phy: nop: Defer clock prepare until PHY init]
removed a goto reaching behind a “return ret” at the end of the function
thus removing the only possible way that statement could be reached, and
so rendering it a dead code.  This commit cleans it up by removing said
dead code.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>