crypto: mediatek - remove redundant bitwise-or

Bitwise-or'ing 0xffffffff with the u32 variable ctr is the same result
as assigning the value to ctr.  Remove the redundant bitwise-or and
just use an assignment.

Addresses-Coverity: ("Suspicious &= or |= constant expression")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>