add extern "C" for cpp

start to work on hal layer

tinyusb/common/compiler/compiler_gcc.h

@@ -49,6 +49,10 @@
 #ifndef _TUSB_COMPILER_GCC_H_
 #define _TUSB_COMPILER_GCC_H_
 
+#ifdef __cplusplus
+ extern "C" {
+#endif
+
 /// Normally, the compiler places the objects it generates in sections like data or bss & function in text. Sometimes, however, you need additional sections, or you need certain particular variables to appear in special sections, for example to map to special hardware. The section attribute specifies that a variable (or function) lives in a particular section
 #define ATTR_SECTION(section) 		 __attribute__ ((#section))
 
@@ -117,6 +121,10 @@
 
 /** @} */
 
+#ifdef __cplusplus
+ }
+#endif
+
 #endif /* _TUSB_COMPILER_GCC_H_ */
 
 /// @}