aarch64: Fix wrong code with st64b builtin [PR110100]

The st64b pattern incorrectly had an output constraint on the register
operand containing the destination address for the store, leading to
wrong code. This patch fixes that.

gcc/ChangeLog:

	PR target/110100
	* config/aarch64/aarch64-builtins.cc (aarch64_expand_builtin_ls64):
	Use input operand for the destination address.
	* config/aarch64/aarch64.md (st64b): Fix constraint on address
	operand.

gcc/testsuite/ChangeLog:

	PR target/110100
	* gcc.target/aarch64/acle/pr110100.c: New test.