cmd/internal/objfile: clean up some comments
cmd/internal/objfile: clean up some comments

Change-Id: Iba6feea74d65a961f30c12fb6c677ccd3b2c3591
Reviewed-on: https://go-review.googlesource.com/106695
Run-TryBot: Josh Bleecher Snyder <cdc248cc4d32e4fbfe04e45228163bcecd48a0b9@gmail.com>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

akutz/go,cloudflare/go,josharian/go,golang/go,akutz/go,CAFxX/go,golang/go,josharian/go,cloudflare/go,josharian/go,nawawi/go,nawawi/go,golang/go,cloudflare/go,CAFxX/go,nawawi/go,akutz/go,golang/go,nawawi/go,akutz/go,josharian/go,josharian/go,josharian/go,nawawi/go,akutz/go,josharian/go,cloudflare/go,cloudflare/go,cloudflare/go,CAFxX/go,cloudflare/go,cloudflare/go,CAFxX/go,akutz/go,CAFxX/go,akutz/go,CAFxX/go,golang/go,CAFxX/go,akutz/go,golang/go,josharian/go,golang/go,nawawi/go,CAFxX/go,nawawi/go,nawawi/go,golang/go