luci-app-ssr-plus: luci-app-ssr-plus.json: Fix `www/cgi-bin/luci` erro issues.

luci-app-ssr-plus/root/usr/share/rpcd/acl.d/luci-app-ssr-plus.json

@@ -2,10 +2,16 @@
 	"luci-app-ssr-plus": {
 		"description": "Grant UCI access for luci-app-ssr-plus",
 		"read": {
+			"file": {
+				"/etc/ssrplus/*": [ "read" ]
+			},
 			"uci": ["shadowsocksr"]
 		},
 		"write": {
+			"file": {
+				"/etc/ssrplus/*": [ "write" ]
+			},
 			"uci": ["shadowsocksr"]
 		}
 	}
-}
+}