Platform: Move Musca-B1 port up by 1 directory

As the Musca-B1 Secure Enclave port was removed there is no need for an
additional subdirectory for the main Musca-B1 port.

Signed-off-by: Mark Horvath <mark.horvath@arm.com>
Change-Id: Ie55deae37cb95de1ddc8569fe57f7ad9f97371bf
diff --git a/docs/platform/arm/index.rst b/docs/platform/arm/index.rst
index 732228a..436518c 100755
--- a/docs/platform/arm/index.rst
+++ b/docs/platform/arm/index.rst
@@ -9,7 +9,7 @@
     Corstone-300 FPGA (AN547) <mps3/an547/README.rst>
     Corstone-300 FPGA and FVP (AN552) <mps3/an552/README.rst>
     Corstone-310 FVP <mps3/corstone310_fvp/README.rst>
-    Musca-B1 <musca_b1/sse_200/readme.rst>
+    Musca-B1 <musca_b1/readme.rst>
     Musca-S1 <musca_s1/readme.rst>
     Runtime Security Subsystem <rss/readme.rst>
 
diff --git a/docs/platform/arm/musca_b1/sse_200/readme.rst b/docs/platform/arm/musca_b1/readme.rst
similarity index 100%
rename from docs/platform/arm/musca_b1/sse_200/readme.rst
rename to docs/platform/arm/musca_b1/readme.rst