Accept both parking-lot 0.11 and 0.12.*, to avoid windows-rs.

In parking_lot 0.12 and parking_lot_core 0.9.0, those crates switched
from the winapi crate to the official Microsoft windows-sys crate.
This is fine, except that windows-sys and its dependencies are even
larger than winapi. Some users may wish to stick with winapi for the
time being; this change allows wgpu to accommodate them.

wgpu-core/Cargo.toml

@@ -30,7 +30,8 @@ codespan-reporting = "0.11"
 copyless = "0.1"
 fxhash = "0.2"
 log = "0.4"
-parking_lot = "0.12"
+# parking_lot 0.12 switches from `winapi` to `windows`; permit either
+parking_lot = ">=0.11,<0.13"
 profiling = { version = "1", default-features = false }
 raw-window-handle = { version = "0.4", optional = true }
 ron = { version = "0.7", optional = true }

wgpu-hal/Cargo.toml

@@ -31,7 +31,8 @@ required-features = ["gles"]
 
 [dependencies]
 bitflags = "1.0"
-parking_lot = "0.12"
+# parking_lot 0.12 switches from `winapi` to `windows`; permit either
+parking_lot = ">=0.11,<0.13"
 profiling = { version = "1", default-features = false }
 raw-window-handle = "0.4"
 thiserror = "1"

wgpu/Cargo.toml

@@ -112,7 +112,8 @@ version = "0.12"
 [dependencies]
 arrayvec = "0.7"
 log = "0.4"
-parking_lot = "0.12"
+# parking_lot 0.12 switches from `winapi` to `windows`; permit either
+parking_lot = ">=0.11,<0.13"
 raw-window-handle = "0.4"
 serde = { version = "1", features = ["derive"], optional = true }
 smallvec = "1"
@@ -283,7 +284,8 @@ web-sys = { version = "0.3.53", features = [
 ]}
 js-sys = "0.3.50"
 wasm-bindgen-futures = "0.4.23"
-parking_lot = "0.12"
+# parking_lot 0.12 switches from `winapi` to `windows`; permit either
+parking_lot = ">=0.11,<0.13"
 
 [target.'cfg(target_arch = "wasm32")'.dev-dependencies]
 console_error_panic_hook = "0.1.6"