Bug fix #6238 and AF_XDP program loading

[joser12345678]

fixed bug by adding program loading support and program unloading after suricata stops. This is done by adding support for adding and removing AF_XDP programs.

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[JR ] I have read the contributing guide lines at https://docs.suricata.io/en/latest/devguide/codebase/contributing/contribution-process.html
[JR ] I have signed the Open Information Security Foundation contribution agreement at https://suricata.io/about/contribution-agreement/
[ JR] I have updated the user guide (in doc/userguide/) to reflect the changes made (if applicable)
Link to redmine ticket:
https://redmine.openinfosecfoundation.org/issues/6238

Describe changes:
fixed bug by adding program loading support and program unloading after suricata stops. This is done by adding support for adding and removing AF_XDP programs. Added RunModeAFXDPRemoveProg() and RunModeLoadAFXDPProg() in runmode-af-xdp.c. Also added flag in the AFXDPIfaceConfig struct called inhibit_prog_load which if true will set a libxdp flag that prevents the default AF_XDP program from being loaded; this is needed if the user wants to load their own AF_XDP program. source-af-xdp.c was also changed to act on this flag being set. The user can now add the "xdp-program" item in the suricata.yaml file to point to a xdp-program the user wishes to load. Finally, added check in suricata.c to unload xdp-programs before the threads are shutdown, which fixes the race condition described in the ticket.

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[joser12345678]

This should fix the compilation errors when AF_XDP is not enabled

[jufajardini]

Previous PR: #9315