scripts: Add libretro core build scripts

scripts/build_libretro_cores.bat

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+@echo off
+echo Updating SCM version...
+pushd %~dp0
+cd ..\src\scmversion
+start /w gen_scmversion.bat
+popd
+
+echo Setting MSVC environment...
+call "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvarsall.bat" x64
+
+echo Creating build directory...
+pushd %~dp0
+cd ..
+if not exist build-libretro mkdir build-libretro
+cd build-libretro
+del /q duckstation_libretro_windows_x64.zip
+rmdir /Q /S windows_x64
+mkdir windows_x64
+cd windows_x64
+
+echo Running CMake...
+cmake -G Ninja -DCMAKE_BUILD_TYPE=Release -DBUILD_LIBRETRO_CORE=ON -DCMAKE_C_COMPILER:FILEPATH="%VCToolsInstallDir%\bin\HostX64\x64\cl.exe" -DCMAKE_CXX_COMPILER:FILEPATH="%VCToolsInstallDir%\bin\HostX64\x64\cl.exe" ..\..
+
+echo Building...
+ninja
+if %errorlevel% neq 0 exit /b %errorlevel%
+
+echo Zipping...
+"C:\Program Files\7-Zip\7z.exe" a ../duckstation_libretro_windows_x64.zip ./duckstation_libretro.dll
+
+echo All done.

scripts/build_libretro_cores.sh

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+#!/usr/bin/env bash
+SCRIPTDIR=$(dirname $(realpath "${BASH_SOURCE[0]}"))
+ROOTDIR=$SCRIPTDIR/..
+BUILDDIR=$SCRIPTDIR/../build-libretro
+set -e
+
+make_build() {
+  PLATFORM=$1
+  OPTIONS=$2
+  SUFFIX=$3
+
+  echo Building for ${PLATFORM}...
+
+  cd $BUILDDIR
+
+  rm -fr $PLATFORM
+  mkdir -p $PLATFORM
+  cd $PLATFORM
+  cmake -G Ninja -DCMAKE_BUILD_TYPE=Release -DBUILD_LIBRETRO_CORE=ON $OPTIONS $ROOTDIR
+
+  ninja
+  rm -f ../duckstation_${PLATFORM}.zip
+  zip -j ../duckstation_${PLATFORM}.zip duckstation_libretro${SUFFIX}.so
+  cd ..
+}
+  
+echo Creating build directory...
+mkdir -p $BUILDDIR
+cd $BUILDDIR || exit $?
+rm -f duckstation_libretro_android_aarch64.zip duckstation_libretro_android_armv7.zip duckstation_libretro_linux_x64.zip duckstation_libretro_linux_aarch64.zip duckstation_libretro_linux_armv7.zip
+
+echo Building...
+make_build linux_x64 "" ""
+make_build linux_aarch64 "-DCMAKE_TOOLCHAIN_FILE=$ROOTDIR/CMakeModules/aarch64-cross-toolchain.cmake" ""
+make_build linux_armv7 "-DCMAKE_TOOLCHAIN_FILE=$ROOTDIR/CMakeModules/armv7-cross-toolchain.cmake" ""
+
+make_build android_aarch64 "-DANDROID_ABI=arm64-v8a -DCMAKE_TOOLCHAIN_FILE=/home/user/Android/ndk-bundle/build/cmake/android.toolchain.cmake" "_android"
+make_build android_armv7 "-DANDROID_ABI=armeabi-v7a -DANDROID_ARM_NEON=ON -DCMAKE_TOOLCHAIN_FILE=/home/user/Android/ndk-bundle/build/cmake/android.toolchain.cmake" "_android"
+