This is the libgcc part of the interface -- providing the functions.
Rationale is provided at the top of libgcc/config/aarch64/lse.S.

	* config/aarch64/lse-init.c: New file.
	* config/aarch64/lse.S: New file.
	* config/aarch64/t-lse: New file.
	* config.host: Add t-lse to all aarch64 tuples.

From-SVN: r275967