bb-reorder.c: Clarify a few points in the head comment and fix long lines in other comments.

	* bb-reorder.c: Clarify a few points in the head comment and fix
	long lines in other comments.
	(find_traces): Fix long line.
	(find_traces_1_round): Likewise.
	(better_edge_p): Likewise.
	(connect_traces): Likewise.
	(duplicate_computed_gotos): Likewise.
	(find_rarely_executed_basic_blocks_and_cr): Remove trailing spaces.
	(fix_up_fall_thru_edges): Fix formatting.

From-SVN: r190979