[Stock] Add cleaner stock

[Stock]
fss0={sd path}
stock=1

Can now work for both older and new HOS versions.

- <= 6.2.0 loads nothing and removes kernel patching.
- >= 7.0.0 loads exo, wb and removes kernel patching.

This requires that fss0 {sd path} is valid. Otherwise it will fail on ini cfg parsing.

If <= 6.2.0 and no FSS0
[Stock]
stock=1

will provide a cleaner stock with no kernel patching.

bootloader/hos/hos.h

@@ -58,7 +58,10 @@ typedef struct _launch_ctxt_t
 
 	bool svcperm;
 	bool debugmode;
+	bool stock;
 	bool atmosphere;
+
+	ini_sec_t *cfg;
 } launch_ctxt_t;
 
 typedef struct _merge_kip_t