Documentation: Fix typo in testing/sysfs-class-cxl

Remove repeated words: "the the lowest" and "this this kernel"

Signed-off-by: Sohaib Mohamed <sohaib.amhmd@gmail.com>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211006155017.135592-1-sohaib.amhmd@gmail.com