The PCIe controller is in an unknown state at driver probe. This can
lead to undesireable effects when the driver attempts to configure the
controller.

Prevent issues in the future by resetting the core during probe.

Link: https://lore.kernel.org/r/20220429123832.2376381-3-pgwipeout@gmail.comTested-by: NNicolas Frattaroli <frattaroli.nicolas@gmail.com>
Signed-off-by: NPeter Geis <pgwipeout@gmail.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>