[NFC] Fix a comment for cfloat128.h (#157093)

Author: c8ef

libc/include/llvm-libc-types/cfloat128.h

@@ -18,7 +18,7 @@
 typedef __typeof__(_Complex __float128) cfloat128;
 #else  // ^^^ workaround / no workaround vvv
 typedef _Complex __float128 cfloat128;
-#endif // ^^^ workaround ^^^
+#endif // ^^^ no workaround ^^^
 #else
 typedef _Complex long double cfloat128;
 #endif // LIBC_TYPES_CFLOAT128_IS_COMPLEX_LONG_DOUBLE