Set jump alignment to 4 for Cortex cores as it reduces codesize by 0.4% on...

Set jump alignment to 4 for Cortex cores as it reduces codesize by 0.4% on...

Set jump alignment to 4 for Cortex cores as it reduces codesize by 0.4% on
average with no obvious performance difference.  See original discussion of
the overheads of various alignments:
https://gcc.gnu.org/ml/gcc-patches/2016-06/msg02075.html.

    gcc/
	* config/aarch64/aarch64.c (cortexa35_tunings): Set jump alignment to 4.
	(cortexa53_tunings): Likewise.
	(cortexa57_tunings): Likewise.
	(cortexa72_tunings): Likewise.
	(cortexa73_tunings): Likewise.

From-SVN: r247609