x86/shutdown: use ACPI reboot method for Dell PowerEdge R540

When EFI booting the Dell PowerEdge R540 it consistently wanders into
the weeds and gets an invalid opcode in the EFI ResetSystem call. This
is the same bug which affects the PowerEdge R740 so fix it in the same
way: quirk this hardware to use the ACPI reboot method instead.

BIOS Information
    Vendor: Dell Inc.
    Version: 1.3.7
    Release Date: 02/09/2018
System Information
    Manufacturer: Dell Inc.
    Product Name: PowerEdge R540

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
master commit: 328ca55b7b
master date: 2018-06-28 09:29:13 +0200

xen/arch/x86/shutdown.c

@@ -477,6 +477,15 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
             DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6520"),
         },
     },
+    {    /* Handle problems with rebooting on Dell PowerEdge R540. */
+        .callback = override_reboot,
+        .driver_data = (void *)(long)BOOT_ACPI,
+        .ident = "Dell PowerEdge R540",
+        .matches = {
+            DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+            DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge R540"),
+        },
+    },
     {    /* Handle problems with rebooting on Dell PowerEdge R740. */
         .callback = override_reboot,
         .driver_data = (void *)(long)BOOT_ACPI,