MDEV-8684: innodb ut_delay - no maths

Reintroduce 3d1a7cba
that removed the maths from ut_delay.

Existing definitions of UT_COMPILE_BARRIER used.
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>

storage/innobase/include/ut0ut.h

@@ -313,7 +313,7 @@ ut_sprintf_timestamp(
 Runs an idle loop on CPU. The argument gives the desired delay
 in microseconds on 100 MHz Pentium + Visual C++.
 @return dummy value */
-ulint
+void
 ut_delay(
 /*=====*/
 	ulint	delay);	/*!< in: delay in microseconds on 100 MHz Pentium */

storage/innobase/ut/ut0ut.cc

@@ -285,26 +285,21 @@ ut_sprintf_timestamp(
 Runs an idle loop on CPU. The argument gives the desired delay
 in microseconds on 100 MHz Pentium + Visual C++.
 @return dummy value */
-ulint
+void
 ut_delay(
 /*=====*/
 	ulint	delay)	/*!< in: delay in microseconds on 100 MHz Pentium */
 {
-	ulint	i, j;
+	ulint	i;
 
 	UT_LOW_PRIORITY_CPU();
 
-	j = 0;
-
 	for (i = 0; i < delay * 50; i++) {
-		j += i;
 		UT_RELAX_CPU();
 		UT_COMPILER_BARRIER();
 	}
 
 	UT_RESUME_PRIORITY_CPU();
-
-	return(j);
 }
 
 /*************************************************************//**