CONFIG_HAVE_KERNEL_UNCOMPRESSED=y is s390 only

Author: cirosantilli

README.adoc

@@ -1344,7 +1344,7 @@ See also: https://stackoverflow.com/questions/2589845/what-are-the-first-operati
 
 <<gem5-tracing>> with `--debug-flags=Exec` does show the right symbols however! So in the worst case, we can just read their source. Amazing.
 
-TODO: try out `CONFIG_HAVE_KERNEL_UNCOMPRESSED=y` from Linux v4.19 and see if it gives us any extra visibility.
+v4.19 also added a `CONFIG_HAVE_KERNEL_UNCOMPRESSED=y` option for having the kernel uncompressed which could make following the startup easier, but it is only available on s390. `aarch64` however is already uncompressed by default, so might be the easiest one: https://unix.stackexchange.com/questions/5518/what-is-the-difference-between-the-following-kernel-makefile-terms-vmlinux-vml/482978#482978
 
 ==== GDB step debug early boot by address