- Fix a typo in the call to acpi_disabled() in probe() by removing an

extra trailing space.
- Don't bother probing a generic ISA bus device if isab0 already exists.
  Some BIOSes place an ACPI psuedo-device with the HID of a generic ISA bus
  device under the PCI-ISA bridge device.  This is not the best solution
  but will work for now.  The isa bus driver only allows for one ISA bus
  anyways.

sys/dev/acpica/acpi_isab.c

@@ -93,7 +93,8 @@ acpi_isab_probe(device_t dev)
 {
 
 	if ((acpi_get_type(dev) == ACPI_TYPE_DEVICE) &&
-	    !acpi_disabled("isa	") &&
+	    !acpi_disabled("isa") &&
+	    devclass_get_device(isab_devclass, 0) == NULL &&
 	    (acpi_MatchHid(dev, "PNP0A05") || acpi_MatchHid(dev, "PNP0A06"))) {
 		device_set_desc(dev, "ACPI Generic ISA bridge");
 		return(0);