Error: LD: symbol not found: '__data_start'

[Alexander Tormasov]

> How do you think about the following fix in this cloudy situation?
> 
> 1. Define __data_start to nil like it's done for _AIX

this will allow compilation, anyway it drop features related to code tracing in go (new helpful debugging capability, as I understand)

> 
> 2. Accept __etext that is already provided by genode_dyn.ld

golang do not report any problems even before last patch, so, I assume that it accept current version (at least compile it)

so, seems that the best solution (safe, no changes in algorithms/data size/etc) seems to be to add these symbols to ldscript as proposed by previous patch.