Remove MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE error code

This error is used when the output buffer isn't large enough
to hold our own certificate.

In the interest of cleaning up the error space for 3.0, this commit
removes MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE and replaces its single
use by MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
diff --git a/include/mbedtls/error.h b/include/mbedtls/error.h
index 5916927..c219d67 100644
--- a/include/mbedtls/error.h
+++ b/include/mbedtls/error.h
@@ -107,8 +107,8 @@
  * SSL       5   2 (Started from 0x5F00)
  * CIPHER    6   8 (Started from 0x6080)
  * SSL       6   24 (Started from top, plus 0x6000)
- * SSL       7   30 (Started from 0x7080, gaps at
- *                   0x7300, 0x7800)
+ * SSL       7   29 (Started from 0x7080, gaps at
+ *                   0x7300, 0x7500, 0x7800)
  *
  * Module dependent error code (5 bits 0x.00.-0x.F8.)
  */
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 2dd6cc4..107a40e 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -71,7 +71,7 @@
 #define MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN                  -0x7380  /**< The server has no ciphersuites in common with the client. */
 #define MBEDTLS_ERR_SSL_NO_RNG                            -0x7400  /**< No RNG was provided to the SSL module. */
 #define MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE             -0x7480  /**< No client certification received from the client, but required by the authentication mode. */
-#define MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE             -0x7500  /**< Our own certificate(s) is/are too large to send in an SSL message. */
+/* NOTE: Error space gap */
 #define MBEDTLS_ERR_SSL_CERTIFICATE_REQUIRED              -0x7580  /**< The own certificate is not set, but needed by the server. */
 #define MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED              -0x7600  /**< The own private key or pre-shared key is not set, but needed. */
 #define MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED                 -0x7680  /**< No CA Chain is set, but required to operate. */