sysctl: avoid inline initialization

sysctl: avoid inline initialization

Assign each field one by one rather than stack initialization as gcc will
call memset() to zero out the rest of the structure -- which we don't care
about as the field is unused and not seen outside of the libc.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Austin Foxley <austinf@cetoncorp.com>