Remove dependencies on xwin and zig.  We're not offering cross-compilation
options using these crates.

diff --git a/Cargo.toml b/Cargo.toml
index 6704e46..ff126a9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -83,16 +83,6 @@ version = "0.1.16"
 [dependencies.cargo-options]
 version = "0.7.2"
 
-[dependencies.cargo-xwin]
-version = "0.16.2"
-optional = true
-default-features = false
-
-[dependencies.cargo-zigbuild]
-version = "0.18.0"
-optional = true
-default-features = false
-
 [dependencies.cargo_metadata]
 version = "0.18.0"
 
@@ -321,8 +311,6 @@ version = "5.0.0"
 [features]
 cli-completion = ["dep:clap_complete_command"]
 cross-compile = [
-    "zig",
-    "xwin",
 ]
 default = [
     "full",
@@ -341,7 +329,6 @@ log = ["tracing-subscriber"]
 native-tls = [
     "dep:native-tls",
     "ureq?/native-tls",
-    "cargo-xwin?/native-tls",
     "dep:rustls-pemfile",
 ]
 password-storage = [
@@ -351,7 +338,6 @@ password-storage = [
 rustls = [
     "dep:rustls",
     "ureq?/tls",
-    "cargo-xwin?/rustls-tls",
     "dep:rustls-pemfile",
 ]
 scaffolding = [
@@ -369,5 +355,3 @@ upload = [
     "wild",
     "dep:dirs",
 ]
-xwin = ["cargo-xwin"]
-zig = ["cargo-zigbuild"]