Initialize a variable in acct_gather_energy/rapl plugin

src/plugins/acct_gather_energy/rapl/acct_gather_energy_rapl.c

@@ -236,7 +236,7 @@ static void _hardware(void)
 {
 	char buf[1024];
 	FILE *fd;
-	int cpu, pkg;
+	int cpu = 0, pkg = 0;
 
 	if ((fd = fopen("/proc/cpuinfo", "r")) == 0)
 		fatal("RAPL: error on attempt to open /proc/cpuinfo");