PATCH: Use LP_SIZE and load timeout pointer into RDX_LP

[Roland McGrath]

> FWIW,  sysdeps/unix/sysv/linux/x86_64/lowlevellock.h has some
> explicit register usages for stack and pointers.  They can use
> R*_LP instead to save a few bytes for x32.

I think it's a good thing to do.  Not just for the few bytes,
but for consistency in what we do or don't truncate to 32 bits.


Thanks,
Roland