sst: Add emr support in sst_mailbox backend

Change-Id: I1192c61827dc573bc0a13cb81a164e37ccb78ca9
Signed-off-by: Jonathan Doman <jonathan.doman@intel.com>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 817b9d1..50be81c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -87,7 +87,7 @@
         add_dependencies (cpuinfoapp libpeci)
         externalproject_add (libpeci PREFIX ${CMAKE_BINARY_DIR}/libpeci
             GIT_REPOSITORY https://github.com/openbmc/libpeci.git
-            GIT_TAG 6a00e9aa72f75d66eb8b9572c7fd3894f91c6bba
+            GIT_TAG 50959a23b48e4f5af9c7110fc78214ea27c6f078
             INSTALL_COMMAND "")
 
         externalproject_get_property (libpeci SOURCE_DIR)
diff --git a/src/sst_mailbox.cpp b/src/sst_mailbox.cpp
index 6024d6d..7b8c156 100644
--- a/src/sst_mailbox.cpp
+++ b/src/sst_mailbox.cpp
@@ -566,7 +566,7 @@
                                                    CPUModel model)
 {
     DEBUG_PRINT << "createMailbox\n";
-    if (model == icx || model == icxd || model == spr)
+    if (model == icx || model == icxd || model == spr || model == emr)
     {
         return std::make_unique<SSTMailbox>(address, model);
     }