cmd/link: set VirtualAddress to 0 for external linker
This is what gcc does when it generates object files.
And pecoff.doc says: "for simplicity, compilers should
set this to zero". It is easier to count everything,
when it starts from 0. Make go linker do the same.
For #10776.
Change-Id: Iffa4b3ad86160624ed34adf1c6ba13feba34c658
Reviewed-on: https://go-review.googlesource.com/36976 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>