Makefile: Add a lint target

The new target just runs all the linters in parallel.

Makefile

@@ -248,6 +248,16 @@ test-all:
 			--rootdir=$(SRCDIR) \
 			-v
 
+#
+# Linting the code
+#
+# Just run `make lint` and see if our linters like your code.
+#
+
+.PHONY: lint
+lint:
+	tox run-parallel -e ruff,pylint,autopep8,isort,mypy
+
 #
 # Building packages
 #