PR gdb/544

	* rltty.c (block_sigint, release_sigint): Rename to...
	(_rl_block_sigint, _rl_release_sigint): ...these and make them global.
	* rltty.h (_rl_block_sigint, _rl_release_sigint): New prototypes.
	* display.c (rl_redisplay): Wrap the function by the calls to
	_RL_BLOCK_SIGINT and _RL_RELEASE_SIGINT.