first rebuild of precise pangolin, including armhf

[Matthias Klose]

This week, a kind of rebuild for precise pangolin in the disguise of the armhf
bootstrap did end.  The build did expose some ARM unspecific build failures;
please use the information from the armhf build logs to address these build
failures. Please use the ftbfs pages to gather more information:

 - http://qa.ubuntuwire.com/ftbfs/ (not yet showing armhf)
   This mostly shows failures introduced by syncs from Debian
   unstable (Debian didn't yet file bug reports after introducing
   the -Werror=format-security default).

 - http://qa.ubuntuwire.org/ftbfs/primary-precise-armhf.html
   Shows armhf and armel build failures. Look at build failures
   which appear on armhf but not armel. These are likely build
   failures for other architectures as well.

There are some generic issues found in more than one package:

 - default CFLAGS/CXXFLAGS include -Werror=format-security.
   Fixes are easy; don't stop fixing the first occurrence, but
   complete a local build.

 - Gnome pkgconfig files dropping -lm from Libs, and other
   packages not explicitly linking with -lm (resulting in symbols
   like "sqrt" and "pow" not found).

 - libreadline-dev dropping build dependency on libncurses-dev,
   and libncurses introducing a new libtinfo library.

ARM (hf) specific issues include

 - compilers not yet built on armhf (gnat, fpc, ocamlopt),
   or not yet having the correct defaults (clang).

 - packaging mentioning armel only, but not armhf; usually
   needs fixes in both the control and rules files.
   http://people.canonical.com/~adconrad/universe-armel-armhf_differences
   might help with these although it includes all the packages
   build depending on gnat and fpc.

 - hard float issues, needing porting work. known ones are
   libreoffice, ocamlopt and fpc, but there will be more ...

The armhf precise archive is installable with debootstrap(1) in a chroot on any
armel Ubuntu/Linaro release.

Thanks to Adam Conrad for driving the bootstrap, to Loic Minier for fixing ARM
issues on the fly, to the Losa's for keeping the build farm alive, and many others.

  Matthias