[patch] Remove linkonce_odr_auto_hide

[Rafael Espíndola]

> I'm in favor of removing dead code, but please don't renumber any enums in the C API - just mark that enum value as dead.  Thanks Rafael,

Hi Chris. I now noticed that this has been broken before. The last
time in r162114. Should I try to get the enums back to their
pre-r162114 value or would that do more harm than good?

Cheers,
Rafael