Fix augmentation pointing to a grouping action's input

When augmentation targets an action input which itself is defined
in a grouping, we need to actually lookup the original definition.

Add a type aliasing information, which should be consulted when
making a simple reference to a type -- and use it in
augmentationToGenTypes().

JIRA: MDSAL-517
Change-Id: I1ef383e8777a7c09a979cbdd84f71be3a0f9b021
Signed-off-by: miroslav.kovac <miroslav.kovac@pantheon.tech>
Signed-off-by: Robert Varga <robert.varga@pantheon.tech>