use proper type for hs_compile_lit's argument

Argument len is size_t, not ulong. Fix the following error on i686-w64-mingw32:
compile_v52.go:40:73: cannot use _Ctype_ulong(len(expression)) (value of type
_Ctype_ulong) as type _Ctype_uint in variable declaration

internal/hs/compile_v52.go

@@ -37,7 +37,7 @@ func CompileLit(expression string, flags CompileFlag, mode ModeFlag, info *Platf
 
 	defer C.free(unsafe.Pointer(expr))
 
-	ret := C.hs_compile_lit(expr, C.uint(flags), C.ulong(len(expression)), C.uint(mode), platform, &db, &err)
+	ret := C.hs_compile_lit(expr, C.uint(flags), C.size_t(len(expression)), C.uint(mode), platform, &db, &err)
 
 	if err != nil {
 		defer C.hs_free_compile_error(err)