Merge pull request #13958 from douardda/patch-1

Fix a typo in STM32F3's CMakeList.txt

Author: 0xc0170

targets/TARGET_STM/TARGET_STM32F3/CMakeLists.txt

@@ -4,7 +4,7 @@
 if("STM32F302x8" IN_LIST MBED_TARGET_LABELS)
     add_subdirectory(TARGET_STM32F302x8)
 elseif("STM32F303x8" IN_LIST MBED_TARGET_LABELS)
-    add_subdirectory(TARGET_TARGET_STM32F303x8)
+    add_subdirectory(TARGET_STM32F303x8)
 elseif("STM32F303xC" IN_LIST MBED_TARGET_LABELS)
     add_subdirectory(TARGET_STM32F303xC)
 elseif("STM32F303xE" IN_LIST MBED_TARGET_LABELS)