package/python3-decorator: use PYTHON3_DECORATOR_VERSION

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/python3-decorator/python3-decorator.mk

@@ -7,7 +7,7 @@
 # Please keep in sync with package/python-decorator/python-decorator.mk
 PYTHON3_DECORATOR_VERSION = 4.4.1
 PYTHON3_DECORATOR_SITE = https://files.pythonhosted.org/packages/dc/c3/9d378af09f5737cfd524b844cd2fbb0d2263a35c11d712043daab290144d
-PYTHON3_DECORATOR_SOURCE = decorator-$(PYTHON_DECORATOR_VERSION).tar.gz
+PYTHON3_DECORATOR_SOURCE = decorator-$(PYTHON3_DECORATOR_VERSION).tar.gz
 PYTHON3_DECORATOR_LICENSE = BSD-2-Clause
 PYTHON3_DECORATOR_LICENSE_FILES = LICENSE.txt
 PYTHON3_DECORATOR_SETUP_TYPE = setuptools