[AArch64] add barriers to ool __sync builtins

[AArch64] add barriers to ool __sync builtins

2022-05-13  Sebastian Pop  <spop@amazon.com>

gcc/
	PR target/105162
	* config/aarch64/aarch64-protos.h (atomic_ool_names): Increase dimension
	of str array.
	* config/aarch64/aarch64.c (aarch64_atomic_ool_func): Call
	memmodel_from_int and handle MEMMODEL_SYNC_*.
	(DEF0): Add __aarch64_*_sync functions.

gcc/testsuite/
	PR target/105162
	* gcc.target/aarch64/sync-comp-swap-ool.c: New.
	* gcc.target/aarch64/sync-op-acquire-ool.c: New.
	* gcc.target/aarch64/sync-op-full-ool.c: New.
	* gcc.target/aarch64/target_attr_20.c: Update check.
	* gcc.target/aarch64/target_attr_21.c: Same.

libgcc/
	PR target/105162
	* config/aarch64/lse.S: Define BARRIER and handle memory MODEL 5.
	* config/aarch64/t-lse: Add a 5th memory model for _sync functions.