net/intel-em-kmod: Update to 7.7.4, enable netmap on 11

[skozlov]

Summary

• Update PORTVERSION and distinfo
• Extend netmap options to slave ports too
• Add option to set maximum supported os version w/netmap for slave ports in intel-ixl-kmod
• Mark the port as non-netmap by default for 12+, as the driver doesn't build with netmap support atm.

Test Plan

Compile and sanity tested using poudriere w/portlint:

intel-em-kmod-7.4.4.log96 KBDownload

intel-ixl-kmod_max_netmap.log91 KBDownload

[franco_opnsense.org]

Looks good, thanks!