For x86, STC still gives better results for optimise-for-size than
"simple" does.  So use STC at -Os as well.


	PR rtl-optimization/67864
	* common/config/i386/i386-common.c (ix86_option_optimization_table)
	<OPT_freorder_blocks_algorithm_>: Use REORDER_BLOCKS_ALGORITHM_STC
	at -Os and up.

From-SVN: r229937