Fix wallpaper and shortcut installation.

builder/stage4/04-pisdr-system/01-run.sh

@@ -1,9 +1,5 @@
-install -m 755 shortcut/gnuradio.desktop "/home/${FIRST_USER_NAME}/Desktop"
-install -m 755 shortcut/gqrx.desktop "/home/${FIRST_USER_NAME}/Desktop"
-install -m 755 shortcut/sdrangel.desktop "/home/${FIRST_USER_NAME}/Desktop"
+install -m 755 shortcut/gnuradio.desktop "${ROOTFS_DIR}/home/${FIRST_USER_NAME}/Desktop"
+install -m 755 shortcut/gqrx.desktop "${ROOTFS_DIR}/home/${FIRST_USER_NAME}/Desktop"
+install -m 755 shortcut/sdrangel.desktop "${ROOTFS_DIR}/home/${FIRST_USER_NAME}/Desktop"
 
-install -m 755 wallpaper/donald-giannatti-vla.jpg "${ROOTFS_DIR}/usr/share/rpd-wallpaper/"
-
-on_chroot << EOF
-pcmanfm --set-wallpaper ${ROOTFS_DIR}/usr/share/rpd-wallpaper/donald-giannatti-vla.jpg
-EOF
+install -m 755 wallpaper/donald-giannatti-vla.jpg "${ROOTFS_DIR}/usr/share/rpd-wallpaper/"