Fix compilation against libpcap-1.0.0.

--- pftop-0.7.orig/bpf_dump.c
+++ pftop-0.7/bpf_dump.c
@@ -33,10 +33,10 @@
 #include <stdio.h>
 
 
-extern void bpf_dump(struct bpf_program *, int);
+extern void bpf_dump(const struct bpf_program *, int);
 
 void
-bpf_dump(struct bpf_program *p, int option)
+bpf_dump(const struct bpf_program *p, int option)
 {
 	struct bpf_insn *insn;
 	int i;
--- pftop-0.7.orig/bpf_filter.c
+++ pftop-0.7/bpf_filter.c
@@ -134,7 +134,7 @@
 }
 #endif
 
-#include <net/bpf.h>
+//#include <net/bpf.h>
 
 /*
  * Execute the filter program starting at pc on the packet p
@@ -143,8 +143,8 @@
  */
 u_int
 bpf_filter(pc, p, wirelen, buflen)
-	struct bpf_insn *pc;
-	u_char *p;
+	const struct bpf_insn *pc;
+	const u_char *p;
 	u_int wirelen;
 	u_int buflen;
 {
--- pftop-0.7.orig/bpf_image.c
+++ pftop-0.7/bpf_image.c
@@ -36,7 +36,7 @@
 
 char *
 bpf_image(p, n)
-	struct bpf_insn *p;
+	const struct bpf_insn *p;
 	int n;
 {
 	int v;
--- pftop-0.7.orig/sf-gencode.h
+++ pftop-0.7/sf-gencode.h
@@ -188,7 +188,7 @@
 const char *sf_get_error(void);
 int sf_compile(struct bpf_program *, char *, int, bpf_u_int32);
 void sf_freecode(struct bpf_program *);
-void bpf_dump(struct bpf_program *, int);
+void bpf_dump(const struct bpf_program *, int);
 
 extern int no_optimize;