debian/control: Add dwarf2sources as dependency

Establish package dwarf2sources as dependency in order to extract source
file names during the strip process performed by dh_strip.

Signed-off-by: Walter Lozano <walter.lozano@collabora.com>

debian/control

@@ -27,6 +27,8 @@ Depends: autotools-dev,
 # dbgsym support landed in 1.18.0, 1.18.2 fixes a related nasty bug.
          dpkg (>= 1.18.0~),
          dpkg-dev (>= 1.18.2~),
+# Apertis extension to extract source file names from binaries
+         dwarf2sources,
          dwz,
          file (>= 3.23),
          libdpkg-perl (>= 1.17.14),