#927 rotor_Test fails on AArch64

[Marcin Juszkiewicz]

Openbabel 2.3.2 testsuite fails on AArch64 (64-bit ARM) under Fedora and Ubuntu distributions:

The following tests FAILED:
10 - rotor_Test (Failed)
23 - inchiSteffen_PubChem.smi_Test (Timeout)
54 - pytest_sym (Timeout)

I looked into rotor test and it looks like issue is in OBRotor::CalcTorsion method. I added bunch of std::cout calls there and compared results with x86-64:

    AArch64                             x86-64

  1:                                 1:
  1: _torsion[0]   = 6               1: _torsion[0]   = 6
  1: _torsion[1]   = 9               1: _torsion[1]   = 9
  1: _torsion[2]   = 12              1: _torsion[2]   = 12
  1: _torsion[3]   = 15              1: _torsion[3]   = 15
  1:                                 1:
  1: v1x       = -1.31002            1: v1x       = -1.31002
  1: v1y       = -0.796717           1: v1y       = -0.796717
  1: v1z       = -0.034437           1: v1z       = -0.034437
  1: v2x       = -1.21398            1: v2x       = -1.21398
  1: v2y       = 0.93634             1: v2y       = 0.93634
  1: v2z       = 0.043099            1: v2z       = 0.043099
  1: v3x       = 0.440074            1: v3x       = 0.440074
  1: v3y       = 1.46771             1: v3y       = 1.46771
  1: v3z       = 0.0653222           1: v3z       = 0.0653222
  1:                                 1:
  1: c1x       = -0.00209297         1: c1x       = -0.00209297
  1: c2x       = -0.00209297         1: c2x       = -0.00209297
  1: c1y       = 0.0982663           1: c1y       = 0.0982663
  1: c2y       = 0.0982663           1: c2y       = 0.0982663
  1: c1z       = -2.19382            1: c1z       = -2.19382
  1: c2z       = -2.19382            1: c2z       = -2.19382
  1: c3x       = -1.18684e-16        1: c3x       = 6.66134e-16
  1: c3y       = 1.0024e-16          1: c3y       = -4.70977e-16
  1: c3z       = 4.61789e-18         1: c3z       = -2.17654e-17
  1:                                 1:
  1: c1mag     = 4.82251             1: c1mag     = 4.82251
  1: c2mag     = 4.82251             1: c2mag     = 4.82251
  1: costheta  = 1                   1: costheta  = 1
  1: ang       = -0.000447214        1: ang       = 0.000447214
  1:                                 1:
  1: -0.000447214                    1: 0.000447214

Same set of tests fail on PPC64 but I did not checked is it same issue.