powercap: intel_rapl: fix UBSAN shift-out-of-bounds issue

In the Linux kernel, the following vulnerability has been resolved:

powercap: intel_rapl: fix UBSAN shift-out-of-bounds issue

When value < time_unit, the parameter of ilog2() will be zero and the return value is -1. u64(-1) is too large for shift exponent and then will trigger shift-out-of-bounds:

shift exponent 18446744073709551615 is too large for 32-bit type 'int' Call Trace: rapl_compute_time_window_core rapl_write_data_raw set_time_window store_constraint_time_window_us