EE: Prevent usage of uninitialized scalar variable

[ssakash]

Quick fix for the following issues,

• CID 153601 (Initial debugger work #1 of 1): Uninitialized scalar variable (UNINIT)7. uninit_use: Using uninitialized value scalarHigh.
• CID 153602 (Initial debugger work #1 of 1): Uninitialized scalar variable (UNINIT)7. uninit_use: Using uninitialized value scalarLow.
• CID 153603 (Initial debugger work #1 of 1): Uninitialized scalar variable (UNINIT)7. uninit_use: Using uninitialized value scalarMid.

Summary of changes:-

• Remove a duplicated check EmuConfig.Speedhacks.EECycleRate == 0 since the check will eventually be done on the switch case statement.
• Prevent a chance for uninitialized variable usage when users set more than 100 in INI file.

actually I thought of fixing these issues at the next update to the overclock function but that would probably take some time so did the fixes now :) , Thanks to @gregory38 for finding the issue.