Manually load X11 and resolve its symbols when needed. This removes the static dependency on X11 on Linux, allowing for headless rendering on systems without it. Bug 20104157 Change-Id: I463c8b3340c3ad16cd0f0d1d0f8804ee31012dd0 Reviewed-on: https://swiftshader-review.googlesource.com/2832 Reviewed-by: Nicolas Capens <capn@google.com> Tested-by: Nicolas Capens <capn@google.com>