Update.

Update.

	* sysdeps/unix/sysv/linux/alpha/bits/types.h: Make __useconds_t
	unsigned.
	* sysdeps/unix/sysv/linux/bits/types.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/bits/types.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/bits/types.h: Likewise.
	* sysdeps/unix/sysv/sysv4/solaris2/bits/types.h: Likewise.

	* sysdeps/generic/bits/types.h: Make __useconds_t unsigned.

	* sysdeps/generic/ualarm.c (ualarm): Change return value and
	parameter type to useconds_t.
	* sysdeps/unix/bsd/ualarm.c: Likewise.

	* sysdeps/generic/usleep.c (usleep): Change parameter type to
	useconds_t.
	* sysdeps/unix/sysv/linux/usleep.c: Likewise.
	* sysdeps/mach/usleep.c: Likewise.