cmd/5g: emit type information in the .5 files

[rsc]

The precise GC needs precise type information in the .5 files, and it's not there. 
Something like https://golang.org/cl/7393061, but that doesn't include
the 5c change (emit another 0) nor the 5l change to read the information.

[minux]

Comment 1:

This issue was updated by revision 8cdee79.

This CL adds gotype into .5 object file.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7376054

[rsc]

Comment 2:

What's left for this issue? That CL looks like it covers it.

[rsc]

Comment 3:

Labels changed: added go1.1maybe, removed go1.1.

[robpike]

Comment 4:

Labels changed: added go1.2maybe, removed go1.1maybe.

[rsc]

Comment 5:

Labels changed: added feature.

[robpike]

Comment 6:

Marking as fixed. Reopen if it's not.

Status changed to Fixed.