gmod_src: Fixed OSX declaring itself as Linux in the console

[garry]

[B]Revision 695[/B]
[INDENT]Fixed OSX declaring itself as Linux in the console[/INDENT] [B]Changed Files:[/B]
[LIST]
[*]trunk/src_garrysmod/game/shared/garrysmod/gmod_lua_system.cpp
[/LIST]

Committed By [B]Garry Newman[/B]