* gnu/packages/maths.scm (arpack-ng): Update to 3.9.0.
[source]: Add 'patches'.
[build-system]: Switch to CMAKE-BUILD-SYSTEM.
[native-inputs]: Remove AUTOCONF, AUTOMAKE, and LIBTOOL.
(arpack-ng-openmpi)[inputs]: Use 'modify-inputs'.
[arguments]: Use gexps.
* gnu/packages/patches/arpack-ng-propagate-rng-state.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
