nir/algebraic: Add unit tests for bitsize validation

The non-failure path can be tested by just compiling mesa and then
testing it, but the failure paths won't be hit unless you make a mistake,
so it's best to test them with some unit tests.

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Dylan Baker <dylan@pnwbakers.com>

src/compiler/nir/meson.build

@@ -262,4 +262,11 @@ if with_tests
     ),
     suite : ['compiler', 'nir'],
   )
+  test(
+    'nir_algebraic_parser',
+    prog_python,
+    args : [
+      join_paths(meson.current_source_dir(), 'tests/algebraic_parser_test.py')
+    ],
+  )
 endif