foam-extend, sundials: add cmake as a builddep

The sundials doesn't use CMake directly, but it is referenced in the
patch step. I suspect it calls CMake somewhere else in its build system.

var/spack/repos/builtin/packages/foam-extend/package.py

@@ -29,6 +29,7 @@ class FoamExtend(Package):
     depends_on('python')
     depends_on('flex@:2.5.99')
     depends_on('zlib')
+    depends_on('cmake', type='build')
 
     depends_on('scotch ~ metis', when='~ptscotch+scotch')
     depends_on('scotch ~ metis + mpi', when='+ptscotch')