Fix NUCLEO_L073RZ target

Author: rwalton-arm

targets/TARGET_STM/TARGET_STM32L0/TARGET_STM32L073xZ/CMakeLists.txt

@@ -5,7 +5,7 @@ add_subdirectory(TARGET_NUCLEO_L073RZ EXCLUDE_FROM_ALL)
 
 if(${MBED_TOOLCHAIN} STREQUAL "GCC_ARM")
     set(STARTUP_FILE TOOLCHAIN_GCC_ARM/startup_stm32l073xx.S)
-    set(LINKER_FILE TOOLCHAIN_GCC_ARM/stm32l073xz.ld)
+    set(LINKER_FILE TOOLCHAIN_GCC_ARM/STM32L073XZ.ld)
 elseif(${MBED_TOOLCHAIN} STREQUAL "ARM")
     set(STARTUP_FILE TOOLCHAIN_ARM/startup_stm32l073xx.S)
     set(LINKER_FILE TOOLCHAIN_ARM/stm32l073xz.sct)