doxygen: fix parameter name typos and misused \p commands

Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/include/mbedtls/ecdsa.h b/include/mbedtls/ecdsa.h
index 7e8a8c1..3b2b418 100644
--- a/include/mbedtls/ecdsa.h
+++ b/include/mbedtls/ecdsa.h
@@ -327,8 +327,8 @@
  * \param md_alg        The hash algorithm used to hash the original data.
  * \param f_rng_blind   The RNG function used for blinding. This must not be
  *                      \c NULL.
- * \param p_rng_blind   The RNG context to be passed to \p f_rng. This may be
- *                      \c NULL if \p f_rng doesn't need a context parameter.
+ * \param p_rng_blind   The RNG context to be passed to \p f_rng_blind. This may be
+ *                      \c NULL if \p f_rng_blind doesn't need a context parameter.
  * \param rs_ctx        The restart context to use. This may be \c NULL
  *                      to disable restarting. If it is not \c NULL, it
  *                      must point to an initialized restart context.