Fixed the for loop condition and judgment condition of the get_cpu_affinity function

[zhangfatboy]

1. Initialization of mask

mask is initialized to 0, but in later code, if (mask! = 0) This condition is meaningless because mask is always 0. This conditional judgment should be removed.

2. The loop condition is incorrect

Loop for (i = 31; i <= 0; The condition of i--) is wrong. i <= 0 causes the loop to terminate immediately because the initial value of i is 31, which does not satisfy the condition of i <= 0. i >= 0 instead.