google-breakpad: integration into Makefile and Config.in

Add a new config option that allows to specify a list of files
to dump symbols from, and generate a database of symbols, in
stagins/usr/share/google-breakpad/.

Signed-off-by: Pascal Huerst <pascal.huerst@gmail.com>
[yann.morin.1998@free.fr: add dependency on the host variant; fix
 script; add commit log]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
[Thomas: remove leftover debugging, rewrap Config.in help text,
propagate dependencies correctly.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>