Docs: Update TF-M repository reference

The TF-M repository has been moved from
  git.trustedfirmware.org/trusted-firmware-m to
  git.trustedfirmware.org/TF-M/trusted-firmware-m

This patch updates references to the documentation
to reflect that change.

Signed-off-by: Minos Galanakis <minos.galanakis@arm.com>

Change-Id: Ib7d4d45bae7790bf69fcad4fd16f558716b20d92
diff --git a/docs/processes/contributing.rst b/docs/processes/contributing.rst
index 321d4be..3708b06 100644
--- a/docs/processes/contributing.rst
+++ b/docs/processes/contributing.rst
@@ -25,7 +25,7 @@
   patch should be posted; follow guidelines below:
 
   - Clone the TF-M code on your own machine from `TF-M git repository
-    <http://git.trustedfirmware.org/trusted-firmware-m.git>`_.
+    <https://git.trustedfirmware.org/TF-M/trusted-firmware-m.git>`_.
   - Follow the :doc:`SW Requirements </docs/user_guides/tfm_sw_requirement>`,
     :doc:`Build Instructions </docs/user_guides/tfm_build_instruction>` and
     :doc:`Coding Guide </docs/about/coding_guide>` for the TF-M project.
@@ -53,7 +53,7 @@
 
     .. code-block:: shell
 
-       git push ssh://review.trustedfirmware.org:29418/trusted-firmware-m.git HEAD:refs/for/master
+       git push ssh://review.trustedfirmware.org:29418/TF-M/trusted-firmware-m.git HEAD:refs/for/master
 
 - Add relevant :doc:`maintainers </docs/about/maintainers>` for reviewing
   the patch.
@@ -66,4 +66,4 @@
 
 --------------
 
-*Copyright (c) 2017-2019, Arm Limited. All rights reserved.*
+*Copyright (c) 2017-2020, Arm Limited. All rights reserved.*