build: curvetun: link against sysctl.o
Fixes curvetun build failure due to undefined reference to
sysctl_get_int in sock.o.
[...]
LD curvetun
curvetun/sock.o: In function `set_system_socket_mem.part.0':
sock.c:(.text+0xc0): undefined reference to `sysctl_set_int'
curvetun/sock.o: In function `set_system_socket_memory':
sock.c:(.text+0x4dd): undefined reference to `sysctl_get_int'
sock.c:(.text+0x505): undefined reference to `sysctl_get_int'
sock.c:(.text+0x52e): undefined reference to `sysctl_get_int'
sock.c:(.text+0x54f): undefined reference to `sysctl_get_int'
collect2: error: ld returned 1 exit status
Signed-off-by: Tobias Geerinckx-Rice <tobias.geerinckx.rice@gmail.com>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>