PCI: tegra: Fix host bridge memory leakage

When probing the PCI host controller driver, if an error occurs, the probe
function code does not free memory allocated for the struct pci_host_bridge
resulting in memory leakage.

Move the struct pci_host_bridge allocation over to the respective devm
interface to fix the issue.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>