Remove unused backtrace function

CMakeLists.txt

@@ -300,11 +300,7 @@ add_boolean_option(UE_DEBUG_TRACE      False "Activate UE debug trace" ON)
 add_boolean_option(UE_TIMING_TRACE     False "Activate UE timing trace" ON)
 
 set (OCP_ITTI ${OPENAIR_DIR}/common/utils/ocp_itti)
-add_library(ITTI
-  ${OCP_ITTI}/intertask_interface.cpp
-  ${OPENAIR_DIR}/common/utils/backtrace.c
-  )
-
+add_library(ITTI ${OCP_ITTI}/intertask_interface.cpp)
 target_link_libraries(ITTI PRIVATE asn1_nr_rrc asn1_lte_rrc)
 
 # asn1c skeletons have hardcoded this flag to make customized debug logs
@@ -783,7 +779,6 @@ add_library(UTIL
   ${OPENAIR_DIR}/common/utils/threadPool/thread-pool.c
   ${OPENAIR_DIR}/common/utils/utils.c
   ${OPENAIR_DIR}/common/utils/system.c
-  ${OPENAIR_DIR}/common/utils/backtrace.c
   ${OPENAIR_DIR}/common/utils/time_meas.c
   ${OPENAIR_DIR}/common/utils/time_stat.c
 )
@@ -2116,7 +2111,6 @@ add_definitions(-DASN1_MINIMUM_VERSION=924)
 # add executables for operation
 #################################
 add_library(minimal_lib
-  ${OPENAIR_DIR}/common/utils/backtrace.c
   ${OPENAIR_DIR}/common/utils/LOG/log.c
   ${OPENAIR_DIR}/common/utils/minimal_stub.c
   ${T_SOURCE}