Use consistent notation in ECDSA_do_verify comments.

Change-Id: Ia0cec71b5f8a6b7f03681b92cfacee13b2a74621
Reviewed-on: https://boringssl-review.googlesource.com/22890
Reviewed-by: Adam Langley <agl@google.com>

crypto/fipsmodule/ecdsa/ecdsa.c

diff --git a/crypto/fipsmodule/ecdsa/ecdsa.c b/crypto/fipsmodule/ecdsa/ecdsa.c
index e34e3bd..0e2adb6 100644
--- a/crypto/fipsmodule/ecdsa/ecdsa.c
+++ b/crypto/fipsmodule/ecdsa/ecdsa.c
@@ -160,7 +160,7 @@
     OPENSSL_PUT_ERROR(ECDSA, ECDSA_R_BAD_SIGNATURE);
     goto err;
   }
-  // calculate tmp1 = inv(S) mod order
+  // tmp = inv(s) mod order
   int no_inverse;
   if (!BN_mod_inverse_odd(u2, &no_inverse, sig->s, order, ctx)) {
     OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB);
@@ -174,7 +174,7 @@
     OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB);
     goto err;
   }
-  // u2 = r * w mod q
+  // u2 = r * tmp mod order
   if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) {
     OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB);
     goto err;