linux chd-rs build, also delete libchdr folder

.gitmodules

@@ -77,6 +77,3 @@
 	path = waterbox/gpgx/Genesis-Plus-GX
 	url = https://github.com/TASEmulators/Genesis-Plus-GX.git
 	branch = tasvideos-2.1
-[submodule "ExternalProjects/libchdr/libchdr"]
-	path = ExternalProjects/libchdr/libchdr
-	url = https://github.com/rtissera/libchdr.git

ExternalProjects/libchdr/.gitignore

@@ -1 +0,0 @@
-build/

ExternalProjects/libchdr/build_release.bat

@@ -1,10 +0,0 @@
-rmdir /s /q build
-mkdir build
-cd build
-:: cl must be used as clang fails to compile :(
-cmake ..\libchdr -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=cl -G Ninja ^
-	-DBUILD_LTO=ON -DBUILD_SHARED_LIBS=ON -DINSTALL_STATIC_LIBS=OFF -DWITH_SYSTEM_ZLIB=OFF
-ninja
-xcopy .\chdr.dll ..\..\..\Assets\dll\ /Y
-xcopy .\chdr.dll ..\..\..\output\dll\ /Y
-cd ..

ExternalProjects/libchdr/build_release.sh

@@ -1,12 +0,0 @@
-#!/bin/sh
-set -e
-if [ -z "$CC" ]; then export CC="clang"; fi
-
-rm -rf build
-mkdir build
-cd build
-cmake ../libchdr -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=$CC -G Ninja \
-	-DBUILD_LTO=ON -DBUILD_SHARED_LIBS=ON -DINSTALL_STATIC_LIBS=OFF -DWITH_SYSTEM_ZLIB=OFF
-ninja
-cp -t ../../../Assets/dll/ ./libchdr.so
-cp -t ../../../output/dll/ ./libchdr.so

ExternalProjects/libchdr/libchdr

@@ -1 +0,0 @@
-Subproject commit 5c598c2df3a7717552a76410d79f5af01ff51b1d