[crypto] Atomize all traces of MbedTLS, and require OpenSSL 3+ (#3606)

Closes #3137
Closes #3465

- Replace all mbedtls usage with OpenSSL
- require OpenSSL
- Up OpenSSL version to 3, cuz that's what we actually need...

CAVEATS:
- httplib also now required
- other ssl backends for svc are unused, maybe remove later
  * To be fair, our CI never used them anyways. And we never tested those

TESTERS PLEASE TEST:
- All games and applets boot
- Boot, load, exit, etc. times

Co-authored-by: crueter <crueter@eden-emu.dev>
Signed-off-by: lizzie <lizzie@eden-emu.dev>
Co-authored-by: crueter <crueter@eden-emu.dev>
Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3606
Reviewed-by: crueter <crueter@eden-emu.dev>
Reviewed-by: MaranBr <maranbr@eden-emu.dev>
Reviewed-by: DraVee <dravee@eden-emu.dev>
Co-authored-by: lizzie <lizzie@eden-emu.dev>
Co-committed-by: lizzie <lizzie@eden-emu.dev>

src/core/hle/service/bcat/bcat_util.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2024 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
@@ -5,7 +8,6 @@
 
 #include <array>
 #include <cctype>
-#include <mbedtls/md5.h>
 
 #include "core/hle/service/bcat/bcat_result.h"
 #include "core/hle/service/bcat/bcat_types.h"

src/core/hle/service/bcat/delivery_cache_directory_service.cpp

@@ -1,9 +1,11 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: Copyright 2024 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
+#include <openssl/err.h>
+#include <openssl/evp.h>
 #include "common/string_util.h"
 #include "core/file_sys/vfs/vfs_types.h"
 #include "core/hle/service/bcat/bcat_result.h"
@@ -18,7 +20,10 @@ namespace Service::BCAT {
 static BcatDigest DigestFile(const FileSys::VirtualFile& file) {
     BcatDigest out{};
     const auto bytes = file->ReadAllBytes();
-    mbedtls_md5(bytes.data(), bytes.size(), out.data());
+
+    u32 hash_len = 0;
+    EVP_Digest(bytes.data(), bytes.size(), out.data(), &hash_len, EVP_md5(), nullptr);
+
     return out;
 }