Fixes #3902: Move r29660 to v1.7 branch (Correct the error check on)

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r29660 [[BR]]
Correct the error check on rml.send

cmr=v1.7.4:reviewer=jsquyres
Fixes #3906: Fix Java bindings on OS X

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r29676 [[BR]]
Don't use the hard-coded name libmpi.so -- instead, use
libmpi.<OPAL_DYN_LIB_SUFFIX>, where OPAL_DYN_LIB_SUFFIX was determined
by configure.

Thanks to Omer Demirel for reporting the issue.

Refs #3905.