godoc: remove dependency of syscall
godoc: remove dependency of syscall

On app-engine, we cannot import syscall.
The respective constants are already defined
elsewhere for the same reason.

R=r, dsymonds
CC=golang-dev
http://codereview.appspot.com/5036042

Triskite/willstone-goclone,bryanxu/go-zh,sanjosh/sanjos100-tipc,webfd/go-zh,bryanxu/go-zh,rflanagan/reginaldflanagan-project1,scirelli/scirelli-go,d0f/go-zh,scirelli/scirelli-go,scirelli/scirelli-go,sanjosh/sanjos100-tipc,webfd/go-zh,sanjosh/sanjos100-tipc,sanjosh/sanjos100-tipc,scirelli/scirelli-go,mhennings/marcohennings-go,webfd/go-zh,glycerine/jeaten-go-arrayof-structof,glycerine/jeaten-go-arrayof-structof,rdp/rogerpack2005-golang,sanjosh/sanjos100-tipc,scirelli/scirelli-go,glycerine/jeaten-go-arrayof-structof,rdp/rogerpack2005-golang,Triskite/willstone-goclone,rflanagan/reginaldflanagan-project1,Triskite/willstone-goclone,d0f/go-zh,mhennings/marcohennings-go,bryanxu/go-zh,webfd/go-zh,mhennings/marcohennings-go,rdp/rogerpack2005-golang,sanjosh/sanjos100-tipc,scirelli/scirelli-go,Triskite/willstone-goclone,bryanxu/go-zh,sanjosh/sanjos100-tipc,d0f/go-zh,glycerine/jeaten-go-arrayof-structof,glycerine/jeaten-go-arrayof-structof,d0f/go-zh,webfd/go-zh,glycerine/jeaten-go-arrayof-structof,mhennings/marcohennings-go,webfd/go-zh,rflanagan/reginaldflanagan-project1,glycerine/jeaten-go-arrayof-structof,scirelli/scirelli-go,mhennings/marcohennings-go,rdp/rogerpack2005-golang,rflanagan/reginaldflanagan-project1,webfd/go-zh,scirelli/scirelli-go,mhennings/marcohennings-go,mhennings/marcohennings-go,bryanxu/go-zh,rflanagan/reginaldflanagan-project1,mhennings/marcohennings-go,Triskite/willstone-goclone,rdp/rogerpack2005-golang,Triskite/willstone-goclone,bryanxu/go-zh,d0f/go-zh,Triskite/willstone-goclone,rflanagan/reginaldflanagan-project1,rflanagan/reginaldflanagan-project1,d0f/go-zh,sanjosh/sanjos100-tipc,d0f/go-zh,glycerine/jeaten-go-arrayof-structof,bryanxu/go-zh,rdp/rogerpack2005-golang,bryanxu/go-zh,rdp/rogerpack2005-golang,rflanagan/reginaldflanagan-project1,Triskite/willstone-goclone,d0f/go-zh,rdp/rogerpack2005-golang,webfd/go-zh