testing/libretro-desmume: remove

Given the numerous number of libretro cores, I've packaged it twice
while it was already present in community/.

testing/libretro-desmume/APKBUILD

-# Contributor: David Demelier <markand@malikania.fr>
-# Maintainer: David Demelier <markand@malikania.fr>
-pkgname=libretro-desmume
-pkgver=0_git20210514
-pkgrel=0
-_commit="0bc055a126a3a5c2a9d0be3181edcc571dcb8ca6"
-pkgdesc="libretro core for desmume"
-url="https://github.com/libretro/desmume"
-arch="all !ppc64le !s390x"
-license="GPL-2.0-only"
-makedepends="libpcap-dev mesa-dev"
-source="$pkgname-$_commit.tar.gz::https://github.com/libretro/desmume/archive/$_commit.tar.gz"
-builddir="$srcdir/desmume-$_commit"
-options="!check" # No tests
-
-case $CARCH in
-arm*)
-	_args="platform=armvhardfloat" ;;
-aarch64)
-	_args="DESMUME_JIT=0" ;;
-esac
-
-build() {
-	make -C desmume/src/frontend/libretro $_args
-}
-
-package() {
-	install -Dm644 desmume/src/frontend/libretro/desmume_libretro.so \
-		"$pkgdir"/usr/lib/libretro/desmume_libretro.so
-}
-
-sha512sums="a2117262840eff762ef46bdd1ebc558b8da7e8cb6d618ff9c543f52db765c89159abf5582c9b299de476a3248fe6d6441d2b2a1015a4c9929345352493fb4cdf  libretro-desmume-0bc055a126a3a5c2a9d0be3181edcc571dcb8ca6.tar.gz"