drivers/ipmi/ipmi_fru: Add missing <stdlib.h>

malloc() needs <stdlib.h>

Change-Id: I0cf6a5b76543cb6dac584de6628cfc459d5a60a8
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37884
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/drivers/ipmi/ipmi_fru.c

@@ -17,6 +17,8 @@
 #include <console/console.h>
 #include <string.h>
 #include <delay.h>
+#include <stdlib.h>
+
 #include "ipmi_ops.h"
 
 #define MAX_FRU_BUSY_RETRY 5