compiler: fix type names for generic named structs

Without this change, the compiler would probably have worked just fine
but the generated types would look odd.

You can see in the test case that it now doesn't use `main.Point` but
rather the correct `main.Poin[float32]` etc.

compiler/compiler.go

@@ -393,7 +393,7 @@ func (c *compilerContext) makeLLVMType(goType types.Type) llvm.Type {
 			// in LLVM IR, named structs are implemented as named structs in
 			// LLVM. This is because it is otherwise impossible to create
 			// self-referencing types such as linked lists.
-			llvmName := typ.Obj().Pkg().Path() + "." + typ.Obj().Name()
+			llvmName := typ.String()
 			llvmType := c.ctx.StructCreateNamed(llvmName)
 			c.llvmTypes.Set(goType, llvmType) // avoid infinite recursion
 			underlying := c.getLLVMType(st)