version: use caret dependencies in Cargo.toml

This is making sure that dependencies are not automatically updated when
new ones are published and keeps the main branch always building.

Signed-off-by: Chao Wu <[email protected]>

Author: studychao

Cargo.toml

@@ -10,8 +10,8 @@ license = "Apache-2.0 OR BSD-3-Clause"
 edition = "2018"
 
 [dependencies]
-vmm-sys-util = ">=0.8.0"
-libc = ">=0.2.39"
+vmm-sys-util = "0.11.0"
+libc = "0.2.39"
 
 [dev-dependencies]
 criterion = "0.3.5"