testing/mcjoin: update config guess for loongarch64

testing/mcjoin/APKBUILD

@@ -11,6 +11,11 @@ subpackages="$pkgname-doc"
 source="https://github.com/troglobit/mcjoin/releases/download/v$pkgver/mcjoin-$pkgver.tar.gz"
 options="!check" # no test suite
 
+prepare() {
+ 	default_prepare
+	update_config_guess
+}
+
 build() {
 	./configure --prefix=/usr
 	make