staging: rtl8188eu: remove MSG_88E macro from include/rtw_debug.h

Remove definition of MSG_88E macro from include/rtw_debug.h, as it
no longer has any callers and does not follow kernel coding conventions.
Removing this macro leaves only RT_TRACE and associated definitions.
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Link: https://lore.kernel.org/r/20210623234902.7411-10-phil@philpotter.co.ukSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8188eu/include/rtw_debug.h

@@ -58,12 +58,6 @@
 
 extern u32 GlobalDebugLevel;
 
-#define MSG_88E(...)							\
-	do {								\
-		if (_drv_err_ <= GlobalDebugLevel)			\
-			pr_info(DRIVER_PREFIX __VA_ARGS__);			\
-	} while (0)
-
 #define RT_TRACE(_comp, _level, fmt)					\
 	do {								\
 		if (_level <= GlobalDebugLevel) {			\