Fix two uninitialized variable warnings

gcc only reports them when compiling with -O3.

src/util/interface.c

@@ -91,7 +91,7 @@ ifaceGetFlags(const char *ifname, short *flags) {
 
 int
 ifaceIsUp(const char *ifname, bool *up) {
-    short flags;
+    short flags = 0;
     int rc = ifaceGetFlags(ifname, &flags);
 
     if (rc)

tools/virsh.c

@@ -2857,7 +2857,7 @@ static bool
 cmdSetvcpus(vshControl *ctl, const vshCmd *cmd)
 {
     virDomainPtr dom;
-    int count;
+    int count = 0;
     bool ret = true;
     int maximum = vshCommandOptBool(cmd, "maximum");
     int config = vshCommandOptBool(cmd, "config");