According to mbedTLS' Changelog "Mbed TLS 3.0.0 branch released
2021-07-07" -> "Removals":
MBEDTLS_ECP_MAX_BITS is no longer a configuration option because it
is now determined automatically based on supported curves.
Hence remove MBEDTLS_ECP_MAX_BITS from configuration files to fix build
issues with Zephyr when there is unfortunate order of include
statements.
Signed-off-by: Marcin Niestroj <m.niestroj@emb.dev>
