lima: lower bool to float when building shaders

lima: lower bool to float when building shaders

Both processors of Mali Utgard are float-only, so bool are not
acceptable data type of them. Fortunately the NIR compiler
infrastructure has a lower pass to lower bool to float.

Call this lower pass to lower bool to float for both GP and PP. This
makes Glamor on Xorg server 1.20.3 at least doesn't hang when starting
gtk3-demo.

The old map of nir op bcsel is changed to fcsel, and the map of b2f32 in
PP is dropped because it's not needed now (it's originally only mapped
to ppir_op_mov).

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Reviewed-by: Qiang Yu <yuq825@gmail.com>