DEBUG_FS was lost way back in v5.5, and EXT4 is used by ast2600 systems
that have MMC.

Link: https://lore.kernel.org/r/20210610045338.99847-1-joel@jms.id.au
Fixes: 0e4a459f ("tracing: Remove unnecessary DEBUG_FS dependency")
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20210603040906.125109-1-joel@jms.id.auSigned-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Olof Johansson <olof@lixom.net>