Remove cmake as a requirement

No longer needed as outlined in #6367

Author: RandomInsano

README.md

@@ -22,7 +22,6 @@ Cargo requires the following tools and packages to build:
 
 * `python`
 * `curl` (on Unix)
-* `cmake`
 * OpenSSL headers (only for Unix, this is the `libssl-dev` package on ubuntu)
 * `cargo` and `rustc`