Fix a fairly common typo in comments
diff --git a/include/mbedtls/ctr_drbg.h b/include/mbedtls/ctr_drbg.h
index a049330..059d3c5 100644
--- a/include/mbedtls/ctr_drbg.h
+++ b/include/mbedtls/ctr_drbg.h
@@ -111,7 +111,7 @@
 
 /**
  * \brief               CTR_DRBG context initialization
- *                      Makes the context ready for mbetls_ctr_drbg_seed() or
+ *                      Makes the context ready for mbedtls_ctr_drbg_seed() or
  *                      mbedtls_ctr_drbg_free().
  *
  * \param ctx           CTR_DRBG context to be initialized