community/libpinyin: disable test_ngram on loongarch64

Add loongarch64 to the list of arches where the test `test_ngram` has
already been disabled. The test failed after multiple retries on the
3.21 loongarch64 builder.

Same issue that was addressed in 0f797f26
for some arches.

community/libpinyin/APKBUILD

@@ -23,7 +23,7 @@ prepare() {
 	default_prepare
 
 	case $CARCH in
-	a*|s390x|x86)
+	a*|loongarch64|s390x|x86)
 		# this test is failing on the package builders for these architectures
 		# but not in CI
 		patch -p1 < "$srcdir"/disable-test_ngram_patch