LINARO: add source repo too

Add the deb-src line too to be able to download package sources.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Change-Id: I3df2e7f4a74f389c23d4a559004cfdf0e1dd9038
diff --git a/files/etc/apt/sources.list.d/linaro.list/LINARO b/files/etc/apt/sources.list.d/linaro.list/LINARO
index 6d82c2c..d73da3f 100644
--- a/files/etc/apt/sources.list.d/linaro.list/LINARO
+++ b/files/etc/apt/sources.list.d/linaro.list/LINARO
@@ -1 +1,2 @@
 deb https://download.opensuse.org/repositories/isv:/linaro:/{%release%}/Debian_{%obs_release%}/ ./
+deb-src https://download.opensuse.org/repositories/isv:/linaro:/{%release%}/Debian_{%obs_release%}/ ./