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)
  *