Fix issue 58135 about _C_LABEL_STRING macro w/o space between literal in C++

Change-Id: Iefc3c090071f3629998515d43907139b07105672
diff --git a/ndk/platforms/android-3/include/sys/cdefs_elf.h b/ndk/platforms/android-3/include/sys/cdefs_elf.h
index 1e57470..5d2e0f3 100644
--- a/ndk/platforms/android-3/include/sys/cdefs_elf.h
+++ b/ndk/platforms/android-3/include/sys/cdefs_elf.h
@@ -32,7 +32,7 @@
 
 #ifdef __LEADING_UNDERSCORE
 #define	_C_LABEL(x)	__CONCAT(_,x)
-#define _C_LABEL_STRING(x)	"_"x
+#define _C_LABEL_STRING(x)	"_" x
 #else
 #define	_C_LABEL(x)	x
 #define _C_LABEL_STRING(x)	x