Fix ec_point_mul_scalar_public's documentation.

At the time the comment was written, the secret multiplication operation
hadn't been split yet.

Change-Id: Idd283461c357b47e91b73fac489d1828c4ce2a0c
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/40065
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>

crypto/fipsmodule/ec/internal.h

diff --git a/crypto/fipsmodule/ec/internal.h b/crypto/fipsmodule/ec/internal.h
index 7934c3a..1d3f9f9 100644
--- a/crypto/fipsmodule/ec/internal.h
+++ b/crypto/fipsmodule/ec/internal.h
@@ -334,9 +334,9 @@
 int ec_point_mul_scalar_base(const EC_GROUP *group, EC_RAW_POINT *r,
                              const EC_SCALAR *scalar);
 
-// ec_point_mul_scalar_public performs the same computation as
-// ec_point_mul_scalar.  It further assumes that the inputs are public so
-// there is no concern about leaking their values through timing.
+// ec_point_mul_scalar_public sets |r| to
+// generator * |g_scalar| + |p| * |p_scalar|. It assumes that the inputs are
+// public so there is no concern about leaking their values through timing.
 OPENSSL_EXPORT int ec_point_mul_scalar_public(const EC_GROUP *group,
                                               EC_RAW_POINT *r,
                                               const EC_SCALAR *g_scalar,