More janitorial work

Install vpp api header files in /usr/include/vpp-api, instead of
/usr/include/api. Someone will eventually complain if we continue with
the status quo.

Generate /usr/bin/vpp_plugin_configure, to correctly configure
standalone plugin compilation against header files installed from the
dev package.

If a plugin's CFLAGS don't precisely match the installed vpp engine
binary, subtle misbehavior can and will occur. Example: the ip4/ip6
main_t structure size / member offsets depend on DPDK=[0|1]. Screw
that one up, and your brand-new configurable ip feature will
mysteriously fail to appear, even though the plugin loads perfectly.

Change-Id: I20c97fe1042808a79935863209d995c31953b98c
Signed-off-by: Dave Barach <dave@barachs.net>
diff --git a/vppapigen/node.c b/vppapigen/node.c
index 30a3b01..449540c 100644
--- a/vppapigen/node.c
+++ b/vppapigen/node.c
@@ -1976,24 +1976,24 @@
     fprintf (fp, 
              "#define vl_api_version(n,v) static u32 %s_api_version %s = v;\n",
 	     vlib_app_name, "__attribute__((unused))");
-    fprintf (fp, "#include <api/%s.api.h>\n", vlib_app_name);
+    fprintf (fp, "#include <vpp-api/%s.api.h>\n", vlib_app_name);
     fprintf (fp, "#undef vl_api_version\n\n");
 
     fprintf (fp, "#include <japi/org_openvpp_vppjapi_vppConn.h>\n");
     fprintf (fp, "#include <japi/org_openvpp_vppjapi_%s.h>\n\n", java_class);
 
-    fprintf (fp, "#include <api/%s_msg_enum.h>\n", vlib_app_name);
+    fprintf (fp, "#include <vpp-api/%s_msg_enum.h>\n", vlib_app_name);
     fprintf (fp, "#define vl_typedefs /* define message structures */\n");
-    fprintf (fp, "#include <api/%s_all_api_h.h> \n", vlib_app_name);
+    fprintf (fp, "#include <vpp-api/%s_all_api_h.h> \n", vlib_app_name);
     fprintf (fp, "#undef vl_typedefs\n\n");
 
     fprintf (fp, "#define vl_endianfun \n");
-    fprintf (fp, "#include <api/%s_all_api_h.h> \n", vlib_app_name);
+    fprintf (fp, "#include <vpp-api/%s_all_api_h.h> \n", vlib_app_name);
     fprintf (fp, "#undef vl_endianfun\n\n");
 
     fprintf (fp, "#define vl_print(handle, ...)\n");
     fprintf (fp, "#define vl_printfun\n");
-    fprintf (fp, "#include <api/%s_all_api_h.h>\n", vlib_app_name);
+    fprintf (fp, "#include <vpp-api/%s_all_api_h.h>\n", vlib_app_name);
     fprintf (fp, "#undef vl_printfun\n\n");
 }