USB: unbreak ehci-mxc on otg port of i.MX27

commit 711669e5 fixed port 0 support
for i.MX51 but broke it for (at least) i.MX27 which doesn't have
a usb_phy1 clock but has a pdev->id 0.

Signed-off-by: Eric Bénard <eric@eukrea.com>
Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>