linux-phytec-ti

pata_it821x: use "const char *" for string literals

Some string literals are pointed to by "char *".  This patch fixes
that.

tj: Updated patch title and description.

Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>