[cmake] refactor: CPM over vcpkg (#250)

Completely replaces vcpkg with CPM for all "system" dependencies. Primarily needed for Android and Windows. Also uses my OpenSSL CI for those two platforms.

In theory, improves configure and build time by a LOT and makes things much easier to manage

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/250
Reviewed-by: Lizzie <lizzie@eden-emu.dev>

.ci/windows/build.sh

@@ -43,17 +43,16 @@ export EXTRA_CMAKE_FLAGS=("${EXTRA_CMAKE_FLAGS[@]}" $@)
 mkdir -p build && cd build
 cmake .. -G Ninja \
     -DCMAKE_BUILD_TYPE="$BUILD_TYPE" \
-	-DENABLE_QT_TRANSLATION=ON \
+    -DENABLE_QT_TRANSLATION=ON \
     -DUSE_DISCORD_PRESENCE=ON \
-    -DYUZU_USE_BUNDLED_SDL2=OFF \
-    -DYUZU_USE_EXTERNAL_SDL2=ON \
+    -DYUZU_USE_BUNDLED_SDL2=ON \
     -DYUZU_TESTS=OFF \
     -DYUZU_CMD=OFF \
     -DYUZU_ROOM_STANDALONE=OFF \
     -DYUZU_USE_QT_MULTIMEDIA=$MULTIMEDIA \
     -DYUZU_USE_QT_WEB_ENGINE=$WEBENGINE \
     -DYUZU_ENABLE_LTO=ON \
-	  "${EXTRA_CMAKE_FLAGS[@]}"
+    "${EXTRA_CMAKE_FLAGS[@]}"
 
 ninja