USB: ehci-fsl: Return valid error in ehci_fsl_setup_phy

ehci_fsl_setup_phy is supposed to return an int, but had a void return
value in the case of controller_ver being invalid.

Introduced by commit 3735ba8d ("powerpc/usb: fix bug of CPU hang
when missing USB PHY clock"), which missed one return.

Signed-off-by: Ben Collins <ben.c@servergy.com>
Cc: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>