Under certain conditions (e.g., building on Fedora 42
using gcc-15.0.1), compilation fails with the following
error:
"error: ‘uint8_t’ does not name a type"
Explicitly include <cstdint> to prevent that situation.
Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
See YosysHQ/yosys#1671 for rationale. Also, added some validation
to our parser, so that out-of-range values are reported and the user
knows they should update yosys.
