ddr: altera: sequencer: Clean checkpatch issues

Fix most of the dangling checkpatch issues, no functional change.
There are still 7 warnings, 1 checks , but those are left in place
for the sake of readability of the code.

Signed-off-by: Marek Vasut <marex@denx.de>
Acked-by: Dinh Nguyen <dinguyen@opensource.altera.com>