testing/stockfish: disable on loongarch64

>>> ERROR: stockfish: Unable to determine architecture from CARCH=loongarch64

testing/stockfish/APKBUILD

@@ -6,9 +6,9 @@ _nnue="5af11540bbfe"
 pkgrel=0
 pkgdesc="Strong chess engine"
 url="https://stockfishchess.org/"
-# s390x: doesn't build
+# s390x, loongarch64: doesn't build
 # ppc64le: fails tests
-arch="all !ppc64le !s390x"
+arch="all !ppc64le !s390x !loongarch64"
 license="GPL-3.0-only"
 checkdepends="bash expect"
 source="$pkgname-$pkgver.tar.gz::https://github.com/official-stockfish/Stockfish/archive/refs/tags/sf_$pkgver.tar.gz