os: update os namespace for 15.0.0, loader/ro: update to use csrng, spl: bump max sessions

stratosphere/ro/ro.json

@@ -15,7 +15,7 @@
 	"filesystem_access":	{
 		"permissions":	"0xFFFFFFFFFFFFFFFF"
 	},
-	"service_access":	["fatal:u", "spl:", "set:sys", "fsp-srv"],
+	"service_access":	["fatal:u", "spl:", "set:sys", "fsp-srv", "csrng"],
 	"service_host":	["ldr:ro", "ro:dmnt", "ro:1"],
 	"kernel_capabilities":	[{
 			"type":	"kernel_flags",