Make SRA qsort comparator transitive

Make SRA qsort comparator transitive

2017-09-26  Martin Jambor  <mjambor@suse.cz>

	* tree-sra.c (compare_access_positions): Put integral types first,
	stabilize sorting of integral types, remove conditions putting
	non-full-precision integers last.
	(sort_and_splice_var_accesses): Disable scalarization if a
	non-integert would be represented by a non-full-precision integer.

From-SVN: r253207