hppa: name setjmp union

Some of the C++ tests want this, and this is what all other arches
have done, so do it on hppa too.

2013-07-07  John David Anglin  <dave.anglin@bell.net>

	* ports/sysdeps/hppa/bits/setjmp.h: Name anonymous union.
hppa: fix build problems with atomic code

Specifically:
../ports/sysdeps/unix/sysv/linux/hppa/bits/atomic.h:68:6: error:
	can’t find a register in class ‘R1_REGS’ while reloading ‘asm’
hppa: fix bug in floating point exception support
hppa: fix pthread spinlock
hppa: fix __O_SYNC to match the kernel
nptl: handle EAGAIN with some futex operations