libc/glibc: do not overwrite existing bits/syscall.h
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Rafael C <groups.r2@gmail.com>
Cc: Jérôme BARDON <bardon.pro@gmail.com>
Cc: Daniel Price <daniel.price@gmail.com>
1 reporter_name="dsreed on freenode/#crosstool-ng"