SFENCE - Throughput and Uops

With unroll_count=500 and no inner loop

Code:
```
   0:	0f ae f8             	sfence 
```
Init:
```
VZEROALL
```
Show nanoBench command
Results:
- MPERF: 20.06
- APERF: 23.0
- UOPS: 4.0
- FpuPipeAssignment.Total0: 0.0
- FpuPipeAssignment.Total1: 0.0
- FpuPipeAssignment.Total2: 0.0
- FpuPipeAssignment.Total3: 0.0
- DIV_CYCLES: 0.0

With loop_count=1000 and unroll_count=10

Code:
```
   0:	0f ae f8             	sfence 
```
Init:
```
VZEROALL
```
Show nanoBench command
Results:
- MPERF: 20.05
- APERF: 23.0
- UOPS: 4.2
- FpuPipeAssignment.Total0: 0.0
- FpuPipeAssignment.Total1: 0.0
- FpuPipeAssignment.Total2: 0.0
- FpuPipeAssignment.Total3: 0.0
- DIV_CYCLES: 0.0

With loop_count=100 and unroll_count=100

Code:
```
   0:	0f ae f8             	sfence 
```
Init:
```
VZEROALL
```
Show nanoBench command
Results:
- MPERF: 20.05
- APERF: 23.0
- UOPS: 4.02
- FpuPipeAssignment.Total0: 0.0
- FpuPipeAssignment.Total1: 0.0
- FpuPipeAssignment.Total2: 0.0
- FpuPipeAssignment.Total3: 0.0
- DIV_CYCLES: 0.0