use embedded-hal-driver keyword for crates.io

acc. to the [awesome-embedded-rust][] list this is the keyword to be
used for embedded drivers.

`dc-motor` isn't really needed as nobody else seems to be using this
keyword and it's mostly covered by the `motor` keyword.

[awesome-embedded-rust]: https://github.com/rust-embedded/awesome-embedded-rust#driver-crates

Author: rursprung

Cargo.toml

@@ -7,7 +7,7 @@ rust-version = "1.60"
 description = "A `no_std` driver for the TB6612FNG motor driver."
 repository = "https://github.com/rursprung/tb6612fng-rs"
 categories = ["embedded", "hardware-support", "no-std"]
-keywords = ["tb6612fng", "driver", "motor", "dc-motor", "controller"]
+keywords = ["tb6612fng", "driver", "motor", "controller", "embedded-hal-driver"]
 license = "MIT OR Apache-2.0"
 
 [dependencies]