package/python-matplotlib: depends on BR2_PACKAGE_PYTHON_NUMPY_ARCH_SUPPORTS

BR2_PACKAGE_PYTHON_MATPLOTLIB selects BR2_PACKAGE_PYTHON_NUMPY, so it
should inherit its dependencies, which includes
BR2_PACKAGE_PYTHON_NUMPY_ARCH_SUPPORTS.

Fixes:
 - http://autobuild.buildroot.org/results/038d50784ec80b35e3daff1966df07a1b52780b3



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