ACPI / resources: only reject zero length resources based at address zero

ACPI / resources: only reject zero length resources based at address zero

The recently merged change (in v3.14-rc6) to ACPI resource detection
(below) causes all zero length ACPI resources to be elided from the
table:

  commit b355cee88e3b1a193f0e9a81db810f6f83ad728b
  Author: Zhang Rui <[email protected]>
  Date:   Thu Feb 27 11:37:15 2014 +0800

    ACPI / resources: ignore invalid ACPI device resources

This change has caused a regression in (at least) serial port detection
for a number of machines (see LP#1313981 [1]).  These seem to represent
their IO regions (presumably incorrectly) as a zero length region.
Reverting the above commit restores these serial devices.

Only elide zero length resources which lie at address 0.

Fixes: b355cee88e3b (ACPI / resources: ignore invalid ACPI device resources)
Signed-off-by: Andy Whitcroft <[email protected]>
Acked-by: Zhang Rui <[email protected]>
Cc: 3.14+ <[email protected]> # 3.14+
Signed-off-by: Rafael J. Wysocki <[email protected]>