Addition of the migration guide entry.
Signed-off-by: TRodziewicz <tomasz.rodziewicz@mobica.com>
diff --git a/docs/3.0-migration-guide.d/remove_SSL_DTLS_BADMAC_LIMIT_option.md b/docs/3.0-migration-guide.d/remove_SSL_DTLS_BADMAC_LIMIT_option.md
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index 0000000..f81bdad
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+Remove MBEDTLS_SSL_DTLS_BADMAC_LIMIT option
+-------------------------------------------
+
+This change does not affect users who used the default `config.h`, as the option
+MBEDTLS_SSL_DTLS_BADMAC_LIMIT was already on by default.
+
+This option was a trade-off between functionality and code size: it allowed
+users who didn't need that feature to avoid paying the cost in code size, by
+disabling it.
+
+This option is no longer present, but its functionality is now always enabled.