glibc misc/sys/cdefs.h nonull - typo in comment

[Jonny Grant]

Hi

There are two small changes I suggest if someone has a moment?

misc/sys/cdefs.h  nonull  - typo in comment
Should be "nonnull"

Also

/posix/glob.c has an unused macro
# define _GL_ARG_NONNULL(params)

Could that be removed?

Seems _GL_ARG_NONNULL is only used in misc/error.c which again just compiles it out. So maybe it can be removed overall in both files?

Kind regards
Jonny