package/python-validators: fix license

The LICENSE file is MIT, not BSD.  The confusion comes from the license info
in setup.py, which stated BSD until (post-0.14.2):

https://github.com/kvesteri/validators/commit/669129a3d3eb106e1b2d82bd9911faebb3287db6

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/python-validators/python-validators.mk

@@ -8,7 +8,7 @@ PYTHON_VALIDATORS_VERSION = 0.14.2
 PYTHON_VALIDATORS_SOURCE = validators-$(PYTHON_VALIDATORS_VERSION).tar.gz
 PYTHON_VALIDATORS_SITE = https://files.pythonhosted.org/packages/4d/56/9b48c918ef118ea12b90f227c4498ed4703b418bdd8fb49479dfcbeae4ef
 PYTHON_VALIDATORS_SETUP_TYPE = setuptools
-PYTHON_VALIDATORS_LICENSE = BSD
+PYTHON_VALIDATORS_LICENSE = MIT
 PYTHON_VALIDATORS_LICENSE_FILES = LICENSE
 
 $(eval $(python-package))