d/control: Build-Depend on linux-image-amd64 [amd64] to allow squashfs tests to run.

Thanks: Marek Marczykowski-Górecki for making me notice they weren't actually running.
Signed-off-by: Mattia Rizzolo <mattia@debian.org>

debian/control

@@ -40,6 +40,7 @@ Build-Depends:
  libjs-jquery-isonscreen <!nocheck>,
  libjs-jquery-tablesorter <!nocheck>,
  libjs-jquery-throttle-debounce <!nocheck>,
+ linux-image-amd64 [amd64] <!nocheck>,
  llvm <!nocheck>,
  lz4 <!nocheck> | liblz4-tool <!nocheck>,
  mono-utils <!nocheck>,