Docs: Consistently refer to Musca-A

Updates documents to consistently refer to Musca-A, rather than using a
mix of Musca-A and Musca-A1.

Change-Id: I6f7a9e6afe3475b4a88200f6e56bf4c5507850e4
Signed-off-by: Jamie Fox <jamie.fox@arm.com>
diff --git a/docs/user_guides/tfm_sw_requirement.rst b/docs/user_guides/tfm_sw_requirement.rst
index 0b2ee22..4ba3a19 100644
--- a/docs/user_guides/tfm_sw_requirement.rst
+++ b/docs/user_guides/tfm_sw_requirement.rst
@@ -264,8 +264,8 @@
 - pyyaml (pip3 install --user pyyaml)
 - jinja2 (pip3 install --user jinja2)
 - Python3 pip
-- `SRecord v1.63 <https://sourceforge.net/projects/srecord/>`__ (for
-  Musca-A1 test chip board)
+- `SRecord v1.63 <https://sourceforge.net/projects/srecord/>`__ (for Musca test
+  chip boards)
 
 Setup Cygwin to enable a compiler toolchain and CMake after installation.
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