[PATCH, testsuite] fix ggcplug.c test-case

[Richard Biener]

On Sun, 11 Jan 2015, Prathamesh Kulkarni wrote:

> Hi,
> The test-case plugin/ggcplug.c was failing due to flattening of tree.h
> and tree-core.h.
> Test-case was incorrect because it included gcc-plugin.h after tree.h whereas
> gcc-plugin.h should be the first header to be included by plugins.

No, it should be definitely included _after_ config.h, system.h
and coretypes.h.

Ok with moving it after coretypes.h.

Thanks,
Richard.