Docs: Intersphinx + Error Fix

Linked TF-M documentation using Intersphinx and fixed Sphinx warnings.

Change-Id: Ia27e7a5e1d81959f628e07412f5e4c1493f5f2e7
Signed-off-by: Elena Uziunaite <elena.uziunaite@arm.com>
diff --git a/docs/tfm_test_suites_addition.rst b/docs/tfm_test_suites_addition.rst
index b27ed74..9f29518 100644
--- a/docs/tfm_test_suites_addition.rst
+++ b/docs/tfm_test_suites_addition.rst
@@ -69,7 +69,7 @@
 ============================
 
 A test configuration controls whether one or multiple test suites are enabled.
-The doc `TF-M Build Instructions <https://tf-m-user-guide.trustedfirmware.org/technical_references/instructions/tfm_build_instruction.html>`_.
+The doc :doc:`TF-M Build Instructions <TF-M:building/tfm_build_instruction>`.
 shows some test configurations which are already supported in current TF-M.
 An example usage of test configuration shows below.
 
@@ -285,7 +285,7 @@
 Some test group may need specific test services. These test services may support
 one or more groups thus developers shall determine the proper test scope. Refer
 to
-`Adding partitions for regression tests <https://git.trustedfirmware.org/TF-M/tf-m-tests.git/tree/docs/tfm_test_services_addition.rst>`_
+:doc:`Adding partitions for regression tests <tfm_test_partitions_addition>`
 to get more information.
 
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