debug: tracing: cmake linker gen for .rtt_buff_data

Add CMake linker generator equialents to what segger_rtt.ld does for
rtt_buff_data

Signed-off-by: Björn Bergman <bjorn.bergman@iar.com>

Author: bjorniuppsala

modules/segger/CMakeLists.txt

@@ -13,6 +13,9 @@ if(CONFIG_USE_SEGGER_RTT)
   zephyr_library_sources_ifdef(CONFIG_SEGGER_SYSTEMVIEW ${SEGGER_DIR}/SEGGER/SEGGER_SYSVIEW.c)
   # Using sort key AAA to ensure that we are placed at start of RAM
   zephyr_linker_sources_ifdef(CONFIG_SEGGER_RTT_SECTION_CUSTOM RAM_SECTIONS SORT_KEY aaa segger_rtt.ld)
+
+  zephyr_linker_section_ifdef(CONFIG_SEGGER_RTT_SECTION_CUSTOM NAME "rtt_buff_data" GROUP RAM_REGION ALIGN 4 NOINPUT)
+  zephyr_linker_section_configure(SECTION "rtt_buff_data" INPUT "${CONFIG_SEGGER_RTT_SECTION_CUSTOM_NAME}" SYMBOLS )
 endif()
 
 if(CONFIG_SEGGER_DEBUGMON)

modules/segger/segger_rtt.ld

@@ -1,3 +1,4 @@
+//Remember to keep this in sync with the cmake file
 SECTION_DATA_PROLOGUE(_RTT_SECTION_NAME,(NOLOAD),)
 {
 __rtt_buff_data_start = .;