[gnome-software] trivial: Fix a -Wmaybe-uninitialized warning

[Kalev Lember <klember src gnome org>]

commit b9b70016f243edd211394f2f667872b8eed1ca22
Author: Kalev Lember <klember redhat com>
Date:   Tue Apr 10 00:16:37 2018 +0200

    trivial: Fix a -Wmaybe-uninitialized warning

 src/gs-shell.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/gs-shell.c b/src/gs-shell.c
index d6121b33..1301b6c4 100644
--- a/src/gs-shell.c
+++ b/src/gs-shell.c
@@ -871,7 +871,7 @@ gs_shell_show_detailed_error (GsShell *shell, const GError *error)
 static gchar *
 get_first_line (const gchar *str)
 {
-       g_auto(GStrv) lines;
+       g_auto(GStrv) lines = NULL;
 
        lines = g_strsplit (str, "\n", 2);
        if (lines != NULL && g_strv_length (lines) != 0)