Fix some issues in comments

Ranging from typos to outdated comment contradicting the code.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/include/mbedtls/pk.h b/include/mbedtls/pk.h
index 28ec29d..48e331a 100644
--- a/include/mbedtls/pk.h
+++ b/include/mbedtls/pk.h
@@ -173,11 +173,11 @@
 
 /* Internal helper to define which fields in the pk_context structure below
  * should be used for EC keys: legacy ecp_keypair or the raw (PSA friendly)
- * format. It should be noticed that this only affects how data is stored, not
+ * format. It should be noted that this only affects how data is stored, not
  * which functions are used for various operations. The overall picture looks
  * like this:
- * - if USE_PSA is not defined and ECP_C is then use ecp_keypair data structure
- *   and legacy functions
+ * - if USE_PSA is not defined and ECP_C is defined then use ecp_keypair data
+ *   structure and legacy functions
  * - if USE_PSA is defined and
  *     - if ECP_C then use ecp_keypair structure, convert data to a PSA friendly
  *       format and use PSA functions
@@ -185,13 +185,13 @@
  *
  * The main reason for the "intermediate" (USE_PSA + ECP_C) above is that as long
  * as ECP_C is defined mbedtls_pk_ec() gives the user a read/write access to the
- * ecp_keypair structure inside the pk_context so he/she can modify it using
+ * ecp_keypair structure inside the pk_context so they can modify it using
  * ECP functions which are not under PK module's control.
  */
 #if defined(MBEDTLS_USE_PSA_CRYPTO) && defined(PSA_WANT_KEY_TYPE_ECC_PUBLIC_KEY) && \
     !defined(MBEDTLS_ECP_C)
 #define MBEDTLS_PK_USE_PSA_EC_DATA
-#endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_ECP_C */
+#endif
 
 /* Helper symbol to state that the PK module has support for EC keys. This
  * can either be provided through the legacy ECP solution or through the
@@ -202,11 +202,11 @@
 
 /* Internal helper to define which fields in the pk_context structure below
  * should be used for EC keys: legacy ecp_keypair or the raw (PSA friendly)
- * format. It should be noted that this only affect how data is stored, not
+ * format. It should be noted that this only affects how data is stored, not
  * which functions are used for various operations. The overall picture looks
  * like this:
- * - if USE_PSA is not defined and ECP_C is then use ecp_keypair data structure
- *   and legacy functions
+ * - if USE_PSA is not defined and ECP_C is defined then use ecp_keypair data
+ *   structure and legacy functions
  * - if USE_PSA is defined and
  *     - if ECP_C then use ecp_keypair structure, convert data to a PSA friendly
  *       format and use PSA functions
@@ -220,11 +220,11 @@
 #if defined(MBEDTLS_USE_PSA_CRYPTO) && defined(PSA_WANT_KEY_TYPE_ECC_PUBLIC_KEY) && \
     !defined(MBEDTLS_ECP_C)
 #define MBEDTLS_PK_USE_PSA_EC_DATA
-#endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_ECP_C */
+#endif
 
 /* Internal helper to define which fields in the pk_context structure below
  * should be used for EC keys: legacy ecp_keypair or the raw (PSA friendly)
- * format. It should be noticed that this only affect how data is stored, not
+ * format. It should be noted that this only affects how data is stored, not
  * which functions are used for various operations. The overall picture looks
  * like this:
  * - if USE_PSA is not defined and ECP_C is then use ecp_keypair data structure
@@ -236,13 +236,13 @@
  *
  * The main reason for the "intermediate" (USE_PSA + ECP_C) above is that as long
  * as ECP_C is defined mbedtls_pk_ec() gives the user a read/write access to the
- * ecp_keypair structure inside the pk_context so he/she can modify it using
+ * ecp_keypair structure inside the pk_context so they can modify it using
  * ECP functions which are not under PK module's control.
  */
 #if defined(MBEDTLS_USE_PSA_CRYPTO) && defined(PSA_WANT_KEY_TYPE_ECC_PUBLIC_KEY) && \
     !defined(MBEDTLS_ECP_C)
 #define MBEDTLS_PK_USE_PSA_EC_DATA
-#endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_ECP_C */
+#endif
 
 /**
  * \brief           Types for interfacing with the debug module