Avoid creating (and subsequently using) fake opt_*.h files
when the modules are built with the kernel and hence actual
opt_*.h files are available in ${KERNBUILDDIR}. Fix a few
small bugs that would prevent this from working.
At last the build options of the modules become consistent
with those of the kernel unless the MODULES_WITH_WORLD way
still is used.
Approved by: re (kensmith, scottl)
Requested by: ru
Tested on: amd64 i386 sparc64
Tested by: md5
src/sys/dev/an/if_an_pccard.c rev 1.10 change requires to include
"card_if.h" but Makefile doesn't know about this file. Without this,
kernel build will fail at this driver.
This means that the kernel can be totally self contained now and is not
dependent on the last buildworld to update /usr/share/mk. This might
also make it easier to build 5.x kernels on 4.0 boxes etc, assuming
gensetdefs and config(8) are updated.