Fix Scalasca build error: (#5004)

Build system "usually" autodetects mpi library but this is
    not the case on many platforms. Provide mpi library name/version
    as part for configure args.

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

@@ -63,4 +63,9 @@ def configure_args(self):
         config_args.append("--with-cube=%s" % spec['cube'].prefix.bin)
         config_args.append("--with-otf2=%s" % spec['otf2'].prefix.bin)
 
+        if self.spec['mpi'].name == 'openmpi':
+            config_args.append("--with-mpi=openmpi")
+        elif self.spec.satisfies('^mpich@3:'):
+            config_args.append("--with-mpi=mpich3")
+
         return config_args