PCI: hv: Don't load the driver for baremetal root partition

The root partition only uses VMBus when running nested.

When running on baremetal the Hyper-V PCI driver is not needed,
so do not initialize it.

Signed-off-by: Mukesh Rathor <mrathor@linux.microsoft.com>
Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Roman Kisel <romank@linux.microsoft.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/1751582677-30930-2-git-send-email-nunodasneves@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <1751582677-30930-2-git-send-email-nunodasneves@linux.microsoft.com>

Author: mrathor99

drivers/pci/controller/pci-hyperv.c

@@ -4144,6 +4144,9 @@ static int __init init_hv_pci_drv(void)
 	if (!hv_is_hyperv_initialized())
 		return -ENODEV;
 
+	if (hv_root_partition() && !hv_nested)
+		return -ENODEV;
+
 	ret = hv_pci_irqchip_init();
 	if (ret)
 		return ret;