Memory allocated l_timeout struct from l_timeout_create not being
freed.
==4184== HEAP SUMMARY:
==4184== in use at exit: 32 bytes in 1 blocks
==4184== total heap usage: 50 allocs, 49 frees, 39,902 bytes allocated
==4184==
==4184== 32 bytes in 1 blocks are definitely lost in loss record 1 of 1
==4184== at 0x4C2ABA0: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==4184== by 0x40706D: l_malloc (util.c:62)
==4184== by 0x408D9A: l_timeout_create (timeout.c:117)
==4184== by 0x40896A: signal_callback (signal.c:82)
==4184== by 0x408692: l_main_run (main.c:346)
==4184== by 0x402474: main (main.c:797)
==4184==
==4184== LEAK SUMMARY:
==4184== definitely lost: 32 bytes in 1 blocks
==4184== indirectly lost: 0 bytes in 0 blocks
==4184== possibly lost: 0 bytes in 0 blocks
==4184== still reachable: 0 bytes in 0 blocks
==4184== suppressed: 0 bytes in 0 blocks
Send a RTM_DELLINK for the interface in use if it was created by iwmon.
As the main loop needs to be running when sending RTM_DELLINK, add a
timeout function for quitting the main loop.
On startup, request a list of interfaces via netlink. Find out whether
an interface of type nlmon exists and use it if it has all the needed
flags set. The default name of the interface is 'nlmon', which can be
changed from the command line. If the interface name is in use and is
not an nlmon type, print out an error message and exit.
