misc/bash/go: remove "doc" subcommand autocompletion
misc/bash/go: remove "doc" subcommand autocompletion

"go doc" has been removed in CL 17799.

LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://codereview.appspot.com/77420045

Committer: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>

rdp/rogerpack2005-golang,webfd/go-zh,rdp/rogerpack2005-golang,rdp/rogerpack2005-golang,rdp/rogerpack2005-golang,rdp/rogerpack2005-golang,bryanxu/go-zh,rdp/rogerpack2005-golang,sanjosh/sanjos100-tipc,d0f/go-zh,d0f/go-zh,sanjosh/sanjos100-tipc,bryanxu/go-zh,d0f/go-zh,d0f/go-zh,d0f/go-zh,sanjosh/sanjos100-tipc,bryanxu/go-zh,rdp/rogerpack2005-golang,webfd/go-zh,sanjosh/sanjos100-tipc,d0f/go-zh,rdp/rogerpack2005-golang,webfd/go-zh,webfd/go-zh,webfd/go-zh,bryanxu/go-zh,d0f/go-zh,sanjosh/sanjos100-tipc,sanjosh/sanjos100-tipc,bryanxu/go-zh,webfd/go-zh,d0f/go-zh,sanjosh/sanjos100-tipc,bryanxu/go-zh,webfd/go-zh,bryanxu/go-zh,sanjosh/sanjos100-tipc,webfd/go-zh,bryanxu/go-zh