Document hal-common as internal

We don't support using it directly (nor do we really want to)

Author: jonas-schievink

nrf-hal-common/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "nrf-hal-common"
 version = "0.10.0"
-description = "Common HAL for the nRF51, nRF52 and nRF91 family of microcontrollers.  More specific HAL crates also exist."
+description = "Implementation details of the nRF HAL crates. Don't use this directly, use one of the specific HAL crates instead (`nrfXYZ-hal`)."
 
 repository = "https://github.com/nrf-rs/nrf-hal"
 authors = [

nrf-hal-common/src/lib.rs

@@ -1,3 +1,6 @@
+//! Implementation details of the nRF HAL crates. Don't use this directly, use one of the specific
+//! HAL crates instead (`nrfXYZ-hal`).
+
 #![no_std]
 
 use embedded_hal as hal;