[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>

externals/CMakeLists.txt

@@ -41,9 +41,6 @@ if (NOT TARGET enet::enet)
     add_library(enet::enet ALIAS enet)
 endif()
 
-# mbedtls
-AddJsonPackage(mbedtls)
-
 # stb
 add_library(stb stb/stb_dxt.cpp)
 target_include_directories(stb PUBLIC ./stb)
@@ -234,9 +231,7 @@ if (VulkanMemoryAllocator_ADDED)
 endif()
 
 # httplib
-if (ENABLE_WEB_SERVICE OR ENABLE_UPDATE_CHECKER OR USE_DISCORD_PRESENCE OR ENABLE_OPENSSL)
-    AddJsonPackage(httplib)
-endif()
+AddJsonPackage(httplib)
 
 # cpp-jwt
 if (ENABLE_WEB_SERVICE OR ENABLE_UPDATE_CHECKER)