lua-decision: throw Lua exception for fatal ruleset errors.

Throw Lua exception to bail out for ruleset generation errors.
Also use mrp_log_error to log errors instead of printf.

Change-Id: I4a760ac6c76df357099207cbe15fa17040034049
lua-decision: use direct dependency on the table for select.

Instead of generating an intermediate target that depends
on the table and have the select rule depend on this one,
omit the intermediate target altogether and let the select
depend on the table itself.

Change-Id: I4b46e9d518843e160a23ae2314c8f28f34e9cb9b
lua-decision: removed now unused 'dependency' Lua object.

Change-Id: Ie9413dd891efc73fe7cf2a6eddefeced0c3a06d2