Add alternate signal stack support to ARM ____longjmp_chk.

	* sysdeps/arm/____longjmp_chk.S: Remove.  Replaced by....
	* sysdeps/unix/sysv/linux/arm/____longjmp_chk.S,
	sysdeps/unix/sysv/linux/arm/eabi/____longjmp_chk.S: This.  New
	files.
	* sysdeps/arm/__longjmp.S, sysdeps/arm/eabi/__longjmp.S: Use r4
	for saved sp.
5 files changed