image: Fixed small image without GPLv3 software

The small packagegroup was missing from the build.
Without the small packagegroup, the image can't be build because were
missing core components like busybox.
Also the multimedia packagegroup was re-added.

classes/seconorth-small-image-nogplv3.bbclass

@@ -18,7 +18,11 @@ IMAGE_FEATURES += " \
 "
 
 IMAGE_INSTALL_GUF += " \
-    packagegroup-guf-debug \
+    packagegroup-guf-small \
+"
+
+IMAGE_INSTALL_MULTIMEDIA += " \
+    packagegroup-guf-multimedia \
 "
 
 IMAGE_INSTALL_TEST += " \
@@ -32,6 +36,7 @@ IMAGE_INSTALL_CONNECTIVITY += " \
 CORE_IMAGE_EXTRA_INSTALL += " \
     ${IMAGE_INSTALL_CONNECTIVITY} \
     ${IMAGE_INSTALL_GUF} \
+    ${IMAGE_INSTALL_MULTIMEDIA} \
     ${IMAGE_INSTALL_TEST} \
 "