Add __fdelt_warn alias

This adds __fdelt_warn as a strong alias of __fdelt_chk, similar to how it is implemented in glibc here: https://sourceware.org/git/?p=glibc.git;a=blob;f=debug/fdelt_chk.c

This was observed to be a requirement of some existing glibc-linked binaries.

Thank you for your time.

Signed-off-by: George Matsumura gm960420@ohio.edu