webkit2gtk: fix build by enabling SSE2 on i686
webkit2gtk: fix build by enabling SSE2 on i686

We already need SSE2 anyway due to gst-plugins-base1, which also uses it.

fixes #11162

[ci skip]

necrophcodr/void-packages,necrophcodr/void-packages,necrophcodr/void-packages,necrophcodr/void-packages,necrophcodr/void-packages