add global support with broken generation function

tests/failing_tests/globals.py

@@ -0,0 +1,23 @@
+import logging
+
+from pythonbpf import compile, bpf, section, bpfglobal, compile_to_ir
+from ctypes import c_void_p, c_int64
+
+@bpf
+@bpfglobal
+def somevalue() -> c_int64:
+    return c_int64(0)
+
+@bpf
+@section("sometag1")
+def sometag(ctx: c_void_p) -> c_int64:
+    return c_int64(0)
+
+@bpf
+@bpfglobal
+def LICENSE() -> str:
+    return "GPL"
+
+
+compile_to_ir("globals.py", "globals.ll", loglevel=logging.INFO)
+compile()