[ar71xx] [ar724x] update to work

• add EARLY_PRINTF for debugging
• update module list to be much larger
• add random, otherwise well, stuff doesn't work.
• IPFIREWALL_DEFAULT_TO_ACCEPT

Tested:

• AP93 (AR7240 + AR9280)

TODO:

• rename to std.AR724X
• unify the built module list between all of the mips24k/mips74k atheros config files - now that the HAL, hwpmc, USB, etc are per-chip/per-arch modules it is easy to just compile them all and only include the ones you care about.