Fixes #3957: Move r29810 to v1.7 branch (Remove non-existent MCA variables from)

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r29810 [[BR]]
Remove non-existent MCA variables from LANL platform file.

No review required.

cmr=v1.7.4:reviewer=ompi-gk1.7
Fixes #3947: Move mxm fixes to v1.7 branch (mtl mxm: update configuration parsing)

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r29797 [[BR]]
mtl mxm: update configuration parsing api to mxm 2.1, drop
older version support (1.0 and 1.1), and cleanup the code.

reviewed by miked.

cmr=v1.7.4:reviewer=ompi-gk1.7
 

r29808 [[BR]]
check for mxm API version >= 1.5
Refs: #3947
Fixes #3926: Move usnic updates to v1.7

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r29714 [[BR]]
Avoid trivial "don't mix declarations and code" compiler warning

r29715 [[BR]]
Help decrease conflicts between SVN trunk and Cisco git branch of OMPI v1.6 branch