<string.h> isn't supposed to be used by the kernel.
cronix.h is <machine/cronix.h>, not "cronyx.h" (ambiguous) or
<sys/cronyx.h> (nonexistent; caused compile to fail).
cxreg.h is <i386/isa/cxreg.h>, not "cxreg.h".
<i386/isa/cpufunc.h> shouldn't be included directly; it is always
included by <sys/systm.h>.
<i386/include/*.h> is <machine/*.h>
<systm.h> is <sys/systm.h>.
<kernel.h> is <sys/kernel.h>.
<bpfilter.h> is "bpfilter.h". It really is in the current directory.