[rygel] core: Fix potential fd leak

[Jens Georg <jensgeorg src gnome org>]

commit 7790cfb5665856d3862b7f55322a526f05014ad0
Author: Jens Georg <mail jensge org>
Date:   Thu Aug 22 20:25:52 2019 +0200

    core: Fix potential fd leak
    
    Part of #137

 src/librygel-core/rygel-energy-management-helper.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/librygel-core/rygel-energy-management-helper.c 
b/src/librygel-core/rygel-energy-management-helper.c
index 8883173a..2f399729 100644
--- a/src/librygel-core/rygel-energy-management-helper.c
+++ b/src/librygel-core/rygel-energy-management-helper.c
@@ -40,7 +40,7 @@ gboolean
 rygel_energy_management_get_mac_and_network_type (const char *iface,
                                                   char      **mac,
                                                   char      **type) {
-    int fd;
+    int fd = -1;
     struct ifreq ifr;
     gboolean retval = FALSE;
 
@@ -82,7 +82,7 @@ rygel_energy_management_get_mac_and_network_type (const char *iface,
 
     retval = TRUE;
 out:
-    if (fd > 0) {
+    if (fd > -1) {
         close (fd);
     }