go/ssa: reduce set of expected indirect imports
go/ssa: reduce set of expected indirect imports

...now that gc's export data records fewer dependencies.

Change-Id: Ie0f68f1f7b0825f6d2c100dfe189be017383db60
Reviewed-on: https://go-review.googlesource.com/22584
Reviewed-by: Robert Griesemer <a6752097faebf1f02d80107d77a9be009089afe3@golang.org>

syreclabs/go-tools,syreclabs/go-tools,syreclabs/go-tools,golang/tools,golang/tools,syreclabs/go-tools,syreclabs/go-tools,golang/tools,golang/tools,syreclabs/go-tools,golang/tools