Fixes #3733: Move r29069, r29071 to v1.7 branch (Enable the use of the Linux memory hooks on Intel MIC)

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r29069 [[BR]]
Enable the use of the Linux memory hooks on Intel MIC.

cmr=v1.7.3:reviewer=jsquyres

r29071 [[BR]]
Also check for /dev/mic/scif when deciding whether to enable the Linux
memory hooks.

The MIC has a /dev/scif device and the host has /dev/mic/scif. I do not
know if this device exists when no MIC is connected.

cmr=v1.7.4:ticket=#3733:reviewer=jsquyres