pkg/debian: Explicitly disable module compression

Upstream sources have changed module compression to zstd. Unfortunately,
that is not supported on older Debian versions. Changing it to xz causes
problems on Ubuntu 23.10. So go back to what we had before: No
compression.

pkg/debian/kernel/ubuntu.config

@@ -10,11 +10,11 @@ CONFIG_DEBUG_INFO_NONE=y
 # CONFIG_DEBUG_INFO_DWARF5 is not set
 
 ##
-## Enforce xz compression (zstd is unavailable on older distros)
+## Disable module compression
 ##
-# CONFIG_MODULE_COMPRESS_NONE is not set
+CONFIG_MODULE_COMPRESS_NONE=y
 # CONFIG_MODULE_COMPRESS_GZIP is not set
-CONFIG_MODULE_COMPRESS_XZ=y
+# CONFIG_MODULE_COMPRESS_XZ is not set
 # CONFIG_MODULE_COMPRESS_ZSTD is not set
 
 ##