cmd/objdump: print full disassembly when testing with -v
cmd/objdump: print full disassembly when testing with -v

It is helpful for debugging.

Change-Id: Idd566d312037420f8341fcf502a45410a8497798
Reviewed-on: https://go-review.googlesource.com/c/go/+/353878
Trust: Josh Bleecher Snyder <cdc248cc4d32e4fbfe04e45228163bcecd48a0b9@gmail.com>
Run-TryBot: Josh Bleecher Snyder <cdc248cc4d32e4fbfe04e45228163bcecd48a0b9@gmail.com>
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

cloudflare/go,CAFxX/go,golang/go,cloudflare/go,nawawi/go,cloudflare/go,cloudflare/go,nawawi/go,nawawi/go,cloudflare/go,CAFxX/go,golang/go,cloudflare/go,golang/go,CAFxX/go,nawawi/go,CAFxX/go,golang/go,CAFxX/go,nawawi/go,nawawi/go,CAFxX/go,golang/go,cloudflare/go,golang/go,CAFxX/go,nawawi/go,golang/go,golang/go,cloudflare/go,nawawi/go,CAFxX/go