fix:fix startip_gcc.c entry point

bsp/tm4c123bsp/libraries/TivaWare_C_series/tm4c123_driverlib/startup/gcc/startup_gcc.c

@@ -291,7 +291,8 @@ ResetISR(void)
     //
     // Call the application's entry point.
     //
-    main();
+    extern int entry(void);
+    entry();
 }
 
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