Ensures sizes are aligned & comparisons are like-to-like in get_unkil_state()

I started looking at this tipped off by the following valgrind warning:
==4572== Invalid read of size 1
==4572==    at 0x10F4CE: get_unkil_state (2bwm.c:328)
==4572==    by 0x10B7BA: main (2bwm.c:717)
==4572==  Address 0x623d500 is 32 bytes inside a block of size 36 free'd
==4572==    at 0x4C289DC: free (in
/usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==4572==    by 0x10F4CD: get_unkil_state (2bwm.c:327)
==4572==    by 0x10B7BA: main (2bwm.c:717)
==4572==
Ensure types and sizes are all aligned in getwmdesktop()

found with valgrind via this warning:
==15230== Invalid read of size 4
==15230==    at 0x10B7AF: main (2bwm.c:303)
==15230==  Address 0x623bdd0 is 32 bytes inside a block of size 36
free'd
==15230==    at 0x4C289DC: free (in
/usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==15230==    by 0x10B7AE: main (2bwm.c:302)