csky: Remove the size from alignment_tbl declaration

csky: Remove the size from alignment_tbl declaration

Having to synchronize the number of ctl_table array elements with the
size in the declaration can lead to discrepancies between the two
values. Since commit d7a76ec87195 ("sysctl: Remove check for sentinel
element in ctl_table arrays"), the calculation of the ctl_table array
size is done solely by the ARRAY_SIZE macro removing the need for the
size in the declaration.

Remove the size for the aligment_tbl declaration and const qualify the
array for good measure.

Signed-off-by: Joel Granados <joel.granados@kernel.org>
Reviewed-by: Kees Cook <kees@kernel.org>