tune-cortexa57-cortexa53: add tunes for ARM Cortex-A53-Cortex-A57

tune-cortexa57-cortexa53: add tunes for ARM Cortex-A53-Cortex-A57

commit 3613b2780a6b5d5d70ea6802be5060a8214cbdb5 from
git://github.com/renesas-rcar/meta-renesas

The renesas rcar SoC H3/M3 is big.LITTLE architecture(cortex-a57.cortex-a53).
In order to optimize the performance of the code running on SoC H3/M3,
add a tune file for ARM Cortex-A53-Cortex-A57.
Create this tune file by refering GCC doc, 3.18.5 ARM Options.

Signed-off-by: Meng Li <Meng.Li@windriver.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>