Remove MBEDTLS_ECDH_COMPUTE_SHARED_ALT

Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h
index 0c9f5e9..a260761 100644
--- a/include/mbedtls/check_config.h
+++ b/include/mbedtls/check_config.h
@@ -185,8 +185,7 @@
 #endif
 
 #if defined(MBEDTLS_ECP_RESTARTABLE)           && \
-    ( defined(MBEDTLS_ECDH_COMPUTE_SHARED_ALT) || \
-      defined(MBEDTLS_ECDSA_SIGN_ALT)          || \
+    ( defined(MBEDTLS_ECDSA_SIGN_ALT)          || \
       defined(MBEDTLS_ECDSA_VERIFY_ALT)        || \
       defined(MBEDTLS_ECDSA_GENKEY_ALT) )
 #error "MBEDTLS_ECP_RESTARTABLE defined, but it cannot coexist with an alternative ECP implementation"
diff --git a/include/mbedtls/mbedtls_config.h b/include/mbedtls/mbedtls_config.h
index 3349d4e..a675f31 100644
--- a/include/mbedtls/mbedtls_config.h
+++ b/include/mbedtls/mbedtls_config.h
@@ -350,7 +350,6 @@
  */
 //#define MBEDTLS_TIMING_ALT
 
-//#define MBEDTLS_ECDH_COMPUTE_SHARED_ALT
 //#define MBEDTLS_ECDSA_VERIFY_ALT
 //#define MBEDTLS_ECDSA_SIGN_ALT
 //#define MBEDTLS_ECDSA_GENKEY_ALT