lima: add hack to flatten control flows in vertex shader

As we currently do not have support for GPIR control flows, we can let
Mesa GLSL code to flatten the control flows in the vertex shader for us.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
38 jobs for !1906 with flatten-cf in 55 minutes and 56 seconds (queued for 5 seconds)
latest merge request