Search modules.builtin file before saying the module was not found.
Note: these "modules" should not appear as dependencies of other modules
(in modules.dep) even if they appear in modinfo. This fixes the return
code of modprobe with builtin modules.
Also fixes a small coding style issue in module_is_inkernel().
When user tries to load a module that is builtin in kernel, modprobe
should just return 0. This is not happening right now, so mark test as
expected_fail until it gets fixed.
Functions that always call exit() should be marked with attribute
noreturn. With glibc this is not necessary, but it fails to compile with
uClibc otherwise.
test 1 - check whether modprobe outputs the right thing when
using --show-depends is used with already loaded modules.
test 2 - check whether modprobe outputs the right thing when
using --show-depends with modules not loaded yet
