Remove redundant assignment in felem_mul_ref in p521
ftmp4 is assigned immediately before receiving the reduced output of the
multiplication of ftmp and ftmp3, without being read inbetween these
assignments. Remove redundant assignment.
@@ -782,7 +782,6 @@ static void felem_inv(felem out, const felem in)
felem_reduce(ftmp3, tmp); /* 2^7 - 2^3 */
felem_square(tmp, ftmp3);
felem_reduce(ftmp3, tmp); /* 2^8 - 2^4 */
- felem_assign(ftmp4, ftmp3);
felem_mul(tmp, ftmp3, ftmp);
felem_reduce(ftmp4, tmp); /* 2^8 - 2^1 */
felem_square(tmp, ftmp4);
