tfm: Use CTR instead of HMAC for RNG

We disable MBEDTLS_CTR_DRBG_C instead of MBEDTLS_HMAC_DRBG_C when
building for TF-M.

We have flash usage issues and HMAC uses much less flash.

It is not clear if there are any users that require CTR and will be
adversely affected by this.

Signed-off-by: Sebastian Bøe <[email protected]>

Author: SebastianBoe

modules/trusted-firmware-m/Kconfig.mbedtls_minimal.defconfig

@@ -21,7 +21,7 @@ config MBEDTLS_DHM_C
 config MBEDTLS_ECP_C
 	default n
 
-config MBEDTLS_HMAC_DRBG_C
+config MBEDTLS_CTR_DRBG_C
 	default n
 
 config MBEDTLS_CIPHER_MODE_CBC