deptypes: mark deptypes in packages

var/spack/repos/builtin/packages/eigen/package.py

@@ -47,7 +47,7 @@ class Eigen(Package):
     variant('mpfr', default=True, description='Enables support for multi-precisions floating points via mpfr')
 
     # TODO : dependency on googlehash, superlu, adolc missing
-    depends_on('cmake')
+    depends_on('cmake', type='build')
     depends_on('metis@5:', when='+metis')
     depends_on('scotch', when='+scotch')
     depends_on('fftw', when='+fftw')