Remove MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH

This commit removes the unused error code

```
MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH
```

from the public API for Mbed TLS 3.0.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
diff --git a/include/mbedtls/error.h b/include/mbedtls/error.h
index c219d67..776013f 100644
--- a/include/mbedtls/error.h
+++ b/include/mbedtls/error.h
@@ -106,7 +106,8 @@
  * HKDF      5   1 (Started from top)
  * SSL       5   2 (Started from 0x5F00)
  * CIPHER    6   8 (Started from 0x6080)
- * SSL       6   24 (Started from top, plus 0x6000)
+ * SSL       6   23 (Started from top, plus 0x6000, gaps at
+ *                   0x6600)
  * SSL       7   29 (Started from 0x7080, gaps at
  *                   0x7300, 0x7500, 0x7800)
  *
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 107a40e..691b0ee 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -111,7 +111,7 @@
 #define MBEDTLS_ERR_SSL_CLIENT_RECONNECT                  -0x6780  /**< The client initiated a reconnect from the same port. */
 #define MBEDTLS_ERR_SSL_UNEXPECTED_RECORD                 -0x6700  /**< Record header looks valid but is not expected. */
 #define MBEDTLS_ERR_SSL_NON_FATAL                         -0x6680  /**< The alert message received indicates a non-fatal error. */
-#define MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH               -0x6600  /**< Couldn't set the hash for verifying CertificateVerify */
+/* NOTE: Error space gap */
 #define MBEDTLS_ERR_SSL_CONTINUE_PROCESSING               -0x6580  /**< Internal-only message signaling that further message-processing should be done */
 #define MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS                 -0x6500  /**< The asynchronous operation is not completed yet. */
 #define MBEDTLS_ERR_SSL_EARLY_MESSAGE                     -0x6480  /**< Internal-only message signaling that a message arrived early. */
diff --git a/library/error.c b/library/error.c
index 039e7be..14aaf3d 100644
--- a/library/error.c
+++ b/library/error.c
@@ -456,8 +456,6 @@
             return( "SSL - Record header looks valid but is not expected" );
         case -(MBEDTLS_ERR_SSL_NON_FATAL):
             return( "SSL - The alert message received indicates a non-fatal error" );
-        case -(MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH):
-            return( "SSL - Couldn't set the hash for verifying CertificateVerify" );
         case -(MBEDTLS_ERR_SSL_CONTINUE_PROCESSING):
             return( "SSL - Internal-only message signaling that further message-processing should be done" );
         case -(MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS):