Revise the SwiftShader makefiles to avoid compile errors

We can get intermittent compile errors with the current makefiles because
the same .cpp is built from multiple Android.mk's. The normal way to resolve
this is to use static libraries to hold the common files.

Change-Id: Ifd39809dfac8c96a622b98ef83f31510b34461e4
Reviewed-on: https://swiftshader-review.googlesource.com/2890
Reviewed-by: Nicolas Capens <capn@google.com>
Tested-by: Greg Hartman <ghartman@google.com>
5 files changed