kconfig: add *.c_shipped back

Fix build error:
  PREPARE build/host/mconf
  CONFIG  build/host/mconf
  gcc: build/host/zconf.tab.c: No such file or directory
  gcc: no input files
kprobes: add kretprobe_register/unregister
kprobe: add documentation
Merge pull request #38 from vh21/master

kconfig: add *.c_shipped back
mk: Kconfig parser is not really generated. Remove the dependency
Merge remote-tracking branch 'arcbbb/dev-kprobes'
kprobes: minor documentation tweaks
kconfig: update .gitignore since we move the generated parsers back
fix typo
kconfig: cleanup building information

Mute the following messages:
gcc -I/usr/include/ncursesw -DCURSES_LOC="<ncursesw/curses.h>" -DLOCALE
-Ibuild/host  -MM *.c > build/host/.depend 2>/dev/null || :
rm build/host/zconf.tab.c
mk: don't touch autoconf.h when exists

autoconf.h will be generated by mconf. There is no need to touch it.
Touch it every time will make the dependency checking failure.
Merge pull request #39 from vh21/master

Clean up building procedure.
organize the descriptions