Split setup target etc.

Makefile

@@ -7,10 +7,14 @@ export CROSS_COMPILE=arm-linux-gnueabi-
 setup:
 	@echo "Updating submodules"
 	@git submodule update --init --recursive
+
+.PHONY:
+setup-dev:
 	@echo "Creating venv"
 	@python3 -m venv env
 	@echo "Installing r3build"
 	@. ./env/bin/activate; \
+	pip install wheel; \
 	pip install r3build
 
 .PHONY:

README.md

@@ -8,6 +8,12 @@ This repository includes:
  - r3build.toml to watch changes that occur in submodules
 
 
+Confirmed environments
+----------------------
+
+- Debian 10 (buster) amd64
+
+
 Getting Started
 ---------------
 
@@ -29,11 +35,6 @@ Getting Started
     $ git submodule update --init --recursive
     ```
 
-1. Then run `make setup` to prepare an build environment. Namely;
-
-    - Python 3 venv in `env`
-    - r3build command in the env
-
 1. Install uuu.
 
     - Follow [the instruction](https://github.com/NXPmicro/mfgtools#linux) and build `uuu` executable.
@@ -65,6 +66,11 @@ Build Linux
 Watch changes in submodules & auto-build
 ----------------------------------------
 
+1. Run `make setup-dev` to prepare a Python venv to watch code changes. Namely;
+
+    - Python 3 venv in `env`
+    - r3build command in the env
+
 1. Run `r3build`. It'll detect the changes you make and builds the corresponding executable automatically.