kernel: Fixed PACKAGE_EXCLUDE for kernel-image

The kernel isn't supposed to be part of the Flash-N-Go-System
ramfs. Since Kirkstone, the old way of removing the kernel doesn't
work anymore. With the PACKAGE_EXCLUDE, the kernel is excluded from
the do_rootfs step.

recipes-bsp/images/fngsystem-image.bb

@@ -86,7 +86,7 @@ IMAGE_INSTALL_FNG:append:mx8m-generic-bsp = " \
 # Since the Kernel is loaded separately anyways, we remove it
 # from the ramfs for now.
 PACKAGE_EXCLUDE = " \
-    kernel-image-5.10.9 \
+    kernel-image-* \
 "
 
 PACKAGE_INSTALL += " \