Add libslirp with glib shim

src/frontend/libslirp/fuzzing/slirp_base_fuzz.h

@@ -0,0 +1,23 @@
+#include <glib.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include "../src/libslirp.h"
+#include "helper.h"
+
+/* Structure for the fuzzers */
+typedef struct pcap_hdr_s {
+    guint32 magic_number; /* magic number */
+    guint16 version_major; /* major version number */
+    guint16 version_minor; /* minor version number */
+    gint32 thiszone; /* GMT to local correction */
+    guint32 sigfigs; /* accuracy of timestamps */
+    guint32 snaplen; /* max length of captured packets, in octets */
+    guint32 network; /* data link type */
+} pcap_hdr_t;
+
+typedef struct pcaprec_hdr_s {
+    guint32 ts_sec; /* timestamp seconds */
+    guint32 ts_usec; /* timestamp microseconds */
+    guint32 incl_len; /* number of octets of packet saved in file */
+    guint32 orig_len; /* actual length of packet */
+} pcaprec_hdr_t;