arm-bsp/trusted-services: pass MM_COMM_BUFFER_SIZE to the libts build

The libts deployment expects the MM Communication buffer size to be
provided using the "MM_COMM_BUFFER_SIZE" variable.
Previously the default value which is set in the [1] was not overridden
here in the recipe because of this.

The size of the MM Communication buffers are not changed in this
commit, the page size is 0x1000.

[1] https://git.trustedfirmware.org/plugins/gitiles/TS/trusted-services.git/+/refs/tags/v1.1.0/deployments/libts/arm-linux/CMakeLists.txt#24

Signed-off-by: Bence Balogh <bence.balogh@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>

meta-arm-bsp/recipes-security/trusted-services/libts_%.bbappend

@@ -1,9 +1,9 @@
 require ts-arm-platforms.inc
 
 EXTRA_OECMAKE:append:corstone1000 = "-DMM_COMM_BUFFER_ADDRESS=0x81FFF000 \
-                                     -DMM_COMM_BUFFER_PAGE_COUNT=1 \
+                                     -DMM_COMM_BUFFER_SIZE=0x1000 \
                                     "
 
 EXTRA_OECMAKE:append:fvp-base = " -DMM_COMM_BUFFER_ADDRESS=0x81000000 \
-                                  -DMM_COMM_BUFFER_PAGE_COUNT=8 \
+                                  -DMM_COMM_BUFFER_SIZE=0x8000 \
     "