Remove MBEDTLS_CHACHA20_ALT

Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
diff --git a/include/mbedtls/mbedtls_config.h b/include/mbedtls/mbedtls_config.h
index 6b36dd7..c1f08f9 100644
--- a/include/mbedtls/mbedtls_config.h
+++ b/include/mbedtls/mbedtls_config.h
@@ -379,7 +379,6 @@
 //#define MBEDTLS_ARIA_ALT
 //#define MBEDTLS_CAMELLIA_ALT
 //#define MBEDTLS_CCM_ALT
-//#define MBEDTLS_CHACHA20_ALT
 //#define MBEDTLS_CMAC_ALT
 //#define MBEDTLS_DES_ALT
 //#define MBEDTLS_GCM_ALT
diff --git a/tests/include/alt-dummy/chacha20_alt.h b/tests/include/alt-dummy/chacha20_alt.h
deleted file mode 100644
index 6fd84d0..0000000
--- a/tests/include/alt-dummy/chacha20_alt.h
+++ /dev/null
@@ -1,16 +0,0 @@
-/* chacha20_alt.h with dummy types for MBEDTLS_CHACHA20_ALT */
-/*
- *  Copyright The Mbed TLS Contributors
- *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
- */
-
-#ifndef CHACHA20_ALT_H
-#define CHACHA20_ALT_H
-
-typedef struct mbedtls_chacha20_context {
-    int dummy;
-}
-mbedtls_chacha20_context;
-
-
-#endif /* chacha20_alt.h */
diff --git a/tf-psa-crypto/drivers/builtin/include/mbedtls/chacha20.h b/tf-psa-crypto/drivers/builtin/include/mbedtls/chacha20.h
index 680fe36..ab7195e 100644
--- a/tf-psa-crypto/drivers/builtin/include/mbedtls/chacha20.h
+++ b/tf-psa-crypto/drivers/builtin/include/mbedtls/chacha20.h
@@ -33,8 +33,6 @@
 extern "C" {
 #endif
 
-#if !defined(MBEDTLS_CHACHA20_ALT)
-
 typedef struct mbedtls_chacha20_context {
     uint32_t MBEDTLS_PRIVATE(state)[16];          /*! The state (before round operations). */
     uint8_t  MBEDTLS_PRIVATE(keystream8)[64];     /*! Leftover keystream bytes. */
@@ -42,10 +40,6 @@
 }
 mbedtls_chacha20_context;
 
-#else  /* MBEDTLS_CHACHA20_ALT */
-#include "chacha20_alt.h"
-#endif /* MBEDTLS_CHACHA20_ALT */
-
 /**
  * \brief           This function initializes the specified ChaCha20 context.
  *
diff --git a/tf-psa-crypto/drivers/builtin/src/chacha20.c b/tf-psa-crypto/drivers/builtin/src/chacha20.c
index acaae5b..3501837 100644
--- a/tf-psa-crypto/drivers/builtin/src/chacha20.c
+++ b/tf-psa-crypto/drivers/builtin/src/chacha20.c
@@ -22,8 +22,6 @@
 
 #include "mbedtls/platform.h"
 
-#if !defined(MBEDTLS_CHACHA20_ALT)
-
 #define ROTL32(value, amount) \
     ((uint32_t) ((value) << (amount)) | ((value) >> (32 - (amount))))
 
@@ -271,8 +269,6 @@
     return ret;
 }
 
-#endif /* !MBEDTLS_CHACHA20_ALT */
-
 #if defined(MBEDTLS_SELF_TEST)
 
 static const unsigned char test_keys[2][32] =