GBE: Reduce random behaviour of the code generation

GBE: Reduce random behaviour of the code generation

There are two major types of random behviour source. One is the
register spill tick. Now we fix it to increase from 0 for
each new code generation.
The second random source is the register sorting. When two
register has the same startID or endID,  their sorting order
is not determined and maybe random in different machine. This
patch mitigate this random source by introduce another comparison
if the main key is identical.

Signed-off-by: Zhigang Gong <zhigang.gong@intel.com>
Reviewed-by: "Song, Ruiling" <ruiling.song@intel.com>