phy: renesas: rcar-gen3-usb2: Fix returning wrong error code

Even if device_create_file() returns error code,
rcar_gen3_phy_usb2_probe() will return zero because the "ret" is
variable shadowing.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/r/202312161021.gOLDl48K-lkp@intel.com/


Fixes: 441a681b ("phy: rcar-gen3-usb2: fix implementation for runtime PM")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20240105093703.3359949-1-yoshihiro.shimoda.uh@renesas.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>