usb: ohci-spear: Remove unnecessary NULL check before clk_disable_unprepare()

clk_disable_unprepare() already checks NULL by using IS_ERR_OR_NULL.
Remove unneeded NULL check for clk here.

Signed-off-by: Chen Ni <[e-mail]>
Acked-by: Alan Stern <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/host/ohci-spear.c

···
 	struct spear_ohci *sohci_p = to_spear_ohci(hcd);
 
 	usb_remove_hcd(hcd);
-	if (sohci_p->clk)
-		clk_disable_unprepare(sohci_p->clk);
+	clk_disable_unprepare(sohci_p->clk);
 
 	usb_put_hcd(hcd);
 }