Make LORAMAC_SECURE_ELEMENT a cache variable and set property strings for GUI

Author: dmeehan1968

as-lib/peripheral/CMakeLists.txt

@@ -7,6 +7,10 @@ if (NOT TARGET ${PROJECT_NAME})
     option(LORAMAC_SECURE_ELEMENT_PRE_PROVISIONED "Secure-element pre-provisioning" ON)
     option(LORAMAC_AES_DEC_PREKEYED "AES DEC Prekeyed" ON)
 
+    set(LORAMAC_SECURE_ELEMENT_LIST SOFT_SE LR1110_SE ATECC608A_TNGLORA_SE)
+    set(LORAMAC_SECURE_ELEMENT SOFT_SE CACHE STRING "Default secure element is SOFT_SE")
+    set_property(CACHE LORAMAC_SECURE_ELEMENT PROPERTY STRINGS ${LORAMAC_SECURE_ELEMENT_LIST})
+
     add_library(${PROJECT_NAME} STATIC)
 
     if (LORAMAC_SECURE_ELEMENT MATCHES SOFT_SE)