i compiled the oleg fw version with uclibc 0.9.19 and bzero is a legacy function in posix 2001.
i still belive if you can compile it with bzero you should be able to use it with the correct librarys. (on my router i am using kamikaze so i can not test dctcs on other fws)
You can try replace bzero with memset:
#define bzero(x, n) memset(x, 0, n);
(you can add the above line in common.h)