make: -3 parameter from https://trac.osgeo.org/grass/changeset/56821 does not help much and is not accepted by python3

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@70273 15284696-431f-4ddb-bdfa-cd5b030d7da7

include/Make/Python.make

@@ -2,4 +2,4 @@
 PY_SOURCES := $(wildcard *.py)
 
 %.pyc: %.py
-	$(PYTHON) -t -3 -m py_compile $<
+	$(PYTHON) -t -m py_compile $<