[AArch64] Add --enable-fix-cortex-a53-835769 configure-time option
* configure.ac: Add --enable-fix-cortex-a53-835769 option.
* configure: Regenerate.
* config/aarch64/aarch64.c (aarch64_override_options): Handle
TARGET_FIX_ERR_A53_835769_DEFAULT.
* config/aarch64/aarch64.opt (mfix-cortex-a53-835769): Set Init
value to 2.
* doc/install.texi (aarch64*-*-*): Document
new --enable-fix-cortex-a53-835769 option.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@216076 138bc75d-0d04-0410-961f-82ee72b054a4