remove unused -DDYNAMIC_DRIVER from c_src/Makefile
remove unused -DDYNAMIC_DRIVER from c_src/Makefile

Thanks to Richard Carlsson for pointing out this unused option.

jgrinstead/yaws,jgrinstead/yaws,jgrinstead/yaws,jgrinstead/yaws,jgrinstead/yaws,jgrinstead/yaws,jgrinstead/yaws