manifest: mbedtls: Update to pick latest config-tls-generic.h

Following recent config patches were merged:
* https://github.com/zephyrproject-rtos/mbedtls/pull/1
config: Allow to enable OpenThread optimizations for mbedTLS
* https://github.com/zephyrproject-rtos/mbedtls/pull/3


configs: config-tls-generic.h: Add CONFIG_MBEDTLS_ECDSA_DETERMINISTIC

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>