PCI: imx6: Simplify a trivial if-return sequence

Simplify a trivial if-return sequence by combining it with a preceding
function call.

The semantic patch that makes this change is available in
scripts/coccinelle/misc/simple_return.cocci.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Lucas Stach <l.stach@pengutronix.de>