trilinos: enable mumps solver in amesos2 if variant is set (#34927)

* enable mumps solver in amesos2 if variant is set for trilinos
* fix formatting

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

@@ -650,6 +650,7 @@ def define_enable(suffix, value=None):
                 ),
                 define_from_variant("Amesos2_ENABLE_Basker", "basker"),
                 define_from_variant("Amesos2_ENABLE_LAPACK", "amesos2"),
+                define_from_variant("Amesos2_ENABLE_MUMPS", "mumps"),
             ]
         )