opal/util/error: check for existing convertor for error range

[hjelmn]

This commit fixes a bug when opal_error_init is called with the same
values multiple times. If opal_error_init is called too many times it
will start failing with OPAL_ERR_OUT_OF_RESOURCE. To fix the problem
check if an existing convertor matching the requested one and return
that one instead.

Signed-off-by: Nathan Hjelm hjelmn@lanl.gov

[hjelmn]

With this commit and either #516 or #517 the following code now works:

for (int i = 0 ; i < 100000 ; ++i) {
    int provided;
    MPI_T_init_thread (MPI_THREAD_SINGLE, &provided);
    MPI_T_finalize ();
}

Not sure why anyone would want to do this but it is allowed by MPI-3.0.

[mellanox-github]

• Coverity found 910 errors for all: http://bgate.mellanox.com:8888/jenkins/job/gh-ompi-master-pr//ws/cov_build/all_427/output/errors/index.html
• Coverity found 5 errors for oshmem: http://bgate.mellanox.com:8888/jenkins/job/gh-ompi-master-pr//ws/cov_build/oshmem_427/output/errors/index.html
• Coverity found 2 errors for fca: http://bgate.mellanox.com:8888/jenkins/job/gh-ompi-master-pr//ws/cov_build/fca_427/output/errors/index.html
  
  Sent from GH.

[mellanox-github]

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Test PASSed.