Boot: Switch boot to use mbed-crypto

Replace the dependency on mbedtls with the version of mbedtls packaged
with mbed-crypto.

Change-Id: I17a68f904c9cd68085ecb4432a7a10d6b64494a1
Signed-off-by: Raef Coles <raef.coles@arm.com>
diff --git a/docs/user_guides/tfm_build_instruction.rst b/docs/user_guides/tfm_build_instruction.rst
index 934b2a5..04de8a5 100644
--- a/docs/user_guides/tfm_build_instruction.rst
+++ b/docs/user_guides/tfm_build_instruction.rst
@@ -28,7 +28,6 @@
 
     cd <TF-M base folder>
     git clone https://git.trustedfirmware.org/trusted-firmware-m.git
-    git clone https://github.com/ARMmbed/mbedtls.git -b mbedtls-2.7.9
     git clone https://github.com/ARMmbed/mbed-crypto.git -b mbedcrypto-1.1.0
     git clone https://github.com/ARM-software/CMSIS_5.git -b 5.5.0
 
@@ -224,8 +223,8 @@
          - ``Release``
          - ``Relwithdebinfo``
          - ``Minsizerel``
-   * - -DMBEDTLS_DEBUG=<ON|OFF>
-     - Enables debug symbols for the Mbed TLS and Mbed Crypto libraries.
+   * - -DMBEDCRYPTO_DEBUG=<ON|OFF>
+     - Enables debug symbols for Mbed Crypto library.
    * - -DBUILD_DWARF_VERSION=<dwarf version>
      - Configures DWARF version.
        The possible values are: