Fix build error on non SSE 4.2 environment
This will fix following error.
```
compiling ../../../../ext/oj/parse.c
../../../../ext/oj/parse.c:366:28: error: too many arguments to function call, expected single argument 'pi', have 2 arguments
scan_string_noSIMD(pi, str);
~~~~~~~~~~~~~~~~~~     ^~~
../../../../ext/oj/parse.c:330:20: note: 'scan_string_noSIMD' declared here
static inline void scan_string_noSIMD(ParseInfo pi) {
```
@@ -363,7 +363,7 @@ static void read_str(ParseInfo pi) {
#if defined(OJ_USE_SSE4_2)
scan_string_SIMD(pi);
#else
- scan_string_noSIMD(pi, str);
+ scan_string_noSIMD(pi);
#endif
if (RB_UNLIKELY(pi->end <= pi->cur)) {
oj_set_error_at(pi,
