Improve code readability while setting link dependencies

Co-authored-by: Hish15 <pharamhector@gmail.com>

cmake/stm32/common.cmake

@@ -229,12 +229,13 @@ function(stm32_add_linker_script TARGET VISIBILITY SCRIPT)
     endif()
 
     get_target_property(LINK_DEPENDS ${TARGET} ${INTERFACE_PREFIX}LINK_DEPENDS)
-    if(LINK_DEPENDS STREQUAL "LINK_DEPENDS-NOTFOUND")
-        set(LINK_DEPENDS "${SCRIPT}")
+    if(LINK_DEPENDS)
+        list(APPEND LINK_DEPENDS "${SCRIPT}")        
     else()
-        list(APPEND LINK_DEPENDS "${SCRIPT}")
+        set(LINK_DEPENDS "${SCRIPT}")
     endif()
 
+
     set_target_properties(${TARGET} PROPERTIES ${INTERFACE_PREFIX}LINK_DEPENDS "${LINK_DEPENDS}")
 endfunction()
 
@@ -273,4 +274,3 @@ include(stm32/l1)
 include(stm32/l4)
 include(stm32/l5)
 
-