python-pyasn: fix legal info

Fixes:
http://autobuild.buildroot.net/results/29c/29ca13a653b2c0cbe449d0b5d795558ce5e4df82/
http://autobuild.buildroot.net/results/5cc/5cc55472682bcb48f732267dd2d9073ce338c294/
http://autobuild.buildroot.net/results/dd9/dd9b087a0e907cbc36f0b870beba375c5fe5b17f/

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/python-pyasn/python-pyasn.mk

@@ -7,8 +7,8 @@
 PYTHON_PYASN_VERSION = 1.6.0b1
 PYTHON_PYASN_SOURCE = pyasn-$(PYTHON_PYASN_VERSION).tar.gz
 PYTHON_PYASN_SITE = https://pypi.python.org/packages/31/da/c8338545be0ee7a727c977113e75888e4f1f2b2e10f9284fdfa31dab29bc
-PYTHON_PYASN_LICENSE = BSD-2c
-PYTHON_PYASN_LICENSE_FILES = LICENSE.txt
+PYTHON_PYASN_LICENSE = MIT, BSD-4c (radix tree)
+PYTHON_PYASN_LICENSE_FILES = LICENSE
 PYTHON_PYASN_SETUP_TYPE = distutils
 
 $(eval $(python-package))