alpha: Stop using 'inorder' and rely entirely on 'minor'

This patch avoids building the 'inorder' CPU model for any permutation
of ALPHA, and also removes the ALPHA regressions using the 'inorder'
CPU. The 'minor' CPU is already providing a broader test coverage.

tests/SConscript

@@ -307,7 +307,6 @@ if env['TARGET_ISA'] == 'alpha':
                 'twosys-tsunami-simple-atomic',
                 'tsunami-o3', 'tsunami-o3-dual',
                 'tsunami-minor', 'tsunami-minor-dual',
-                'tsunami-inorder',
                 'tsunami-switcheroo-full']
 if env['TARGET_ISA'] == 'sparc':
     configs += ['t1000-simple-atomic',