[lanai] Handle atomic load of i8 like regular load.
[lanai] Handle atomic load of i8 like regular load.

Loads and stores less than 64-bits are already atomic, this adds support for a special case thereof. This needs to be expanded.



git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@336236 91177308-0d34-0410-b5e6-96231b3b80d8

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