Support multiple/alternative table definitions

[jphickey]

Is your feature request related to a problem? Please describe.
Some users have requested the ability to generate multiple different table files/configurations as part of the build, to represent different hardware configurations. This way, they can choose the active configuration at install time (by choosing which file gets copied to the target) or at run time, by loading a different table file.

Describe the solution you'd like
Currently the "add_cfe_tables" does not directly support this, but with a little work it should be able to. This requires adding an "install" hook so the user has a proper place to call this function to generate customized table files.

Describe alternatives you've considered
While this is possible to some degree with the current build system, all decisions are made at build time. For instance the C preprocessor can be used (via e.g. add_definitions) to select different table values based on build-time configurations. Alternatively, the user can write their own script to compile a C file and call elf2cfetbl on it, but it can be difficult to determine the proper include paths and compile definitions.

Requester Info
Joseph Hickey, Vantage Systems, Inc.