[i-g-t] tests/intel/i915_suspend: Fix WARNs of invalid fd

[Bhanuprakash Modem <bhanuprakash.modem@intel.com>]

Call drm_close_driver() only if fd >=0, otherwise it'll will throw WARN:

(i915_suspend:7563) drmtest-WARNING: Don't attempt to close standard/invalid file descriptor: -1

Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem@intel.com>
---
 tests/intel/i915_suspend.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tests/intel/i915_suspend.c b/tests/intel/i915_suspend.c
index c25805584..82cabfa41 100644
--- a/tests/intel/i915_suspend.c
+++ b/tests/intel/i915_suspend.c
@@ -300,7 +300,9 @@ test_suspend_without_i915(int state)
 		igt_pm_get_d3cold_allowed(card.pci_slot_name, &d3cold_allowed);
 		igt_pm_set_d3cold_allowed(card.pci_slot_name, 0);
 	}
-	drm_close_driver(fd);
+
+	if (fd >= 0)
+		drm_close_driver(fd);
 
 	igt_kmsg(KMSG_INFO "Unloading i915\n");
 	igt_assert_eq(igt_i915_driver_unload(),0);
-- 
2.40.0