ACPI / x86: boot: Propagate error code in acpi_gsi_to_irq()

acpi_get_override_irq() followed by acpi_register_gsi() returns negative
error code on failure.

Propagate it from acpi_gsi_to_irq() to callers.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
[ rjw : Subject/changelog ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

arch/x86/kernel/acpi/boot.c

@@ -619,17 +619,17 @@ int acpi_gsi_to_irq(u32 gsi, unsigned int *irqp)
 	}
 
 	rc = acpi_get_override_irq(gsi, &trigger, &polarity);
-	if (rc == 0) {
-		trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
-		polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
-		irq = acpi_register_gsi(NULL, gsi, trigger, polarity);
-		if (irq >= 0) {
-			*irqp = irq;
-			return 0;
-		}
-	}
+	if (rc)
+		return rc;
 
-	return -1;
+	trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
+	polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
+	irq = acpi_register_gsi(NULL, gsi, trigger, polarity);
+	if (irq < 0)
+		return irq;
+
+	*irqp = irq;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);