[update] target defaults.

Author: vmarcella

crates/lambda-rs-platform/Cargo.toml

@@ -43,17 +43,17 @@ gfx-with-dx12=["dep:gfx-backend-dx12"]
 crate-type = ["cdylib", "rlib"]
 incremental = true
 
-[target.'cfg(all(unix, not(target_os = "macos")))'.dependencies.default_backend]
+[target.'cfg(all(unix, not(target_os = "macos"), not(feature = "gfx-with-opengl")))'.dependencies.default_backend]
 package = "gfx-backend-gl"
 version = "=0.9.0"
 optional = true
 
-[target.'cfg(all(target_os = "macos"))'.dependencies.default_backend]
+[target.'cfg(all(target_os = "macos", not(feature = "gfx-with-metal")))'.dependencies.default_backend]
 package = "gfx-backend-metal"
 version = "=0.9.0"
 optional = true
 
-[target.'cfg(all(windows))'.dependencies.default_backend]
+[target.'cfg(all(windows, not(feature = "gfx-with-dx12")))'.dependencies.default_backend]
 package = "gfx-backend-dx12"
 version = "=0.9.0"
 optional = true