perf cpumap: Make counter as unsigned ints

perf cpumap: Make counter as unsigned ints

These are loop counters which is inherently unsigned. Therefore make
them unsigned. Moreover it also fixes alloc-size-larger-than
error with gcc-13, where malloc can be called with (-1) due to tmp_len
being an int type.

Fixes
| cpumap.c:366:20: error: argument 1 range [18446744065119617024, 18446744073709551612] exceeds maximum object size 9223372036854775807 [-Werror=alloc-size-larger-than=]
|   366 |         tmp_cpus = malloc(tmp_len * sizeof(struct perf_cpu));
|       |                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Upstream-Status: Submitted [https://lore.kernel.org/linux-perf-users/20230123211310.127532-1-raj.khem@gmail.com/T/#u]

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Change-Id: I7ecc661339efd49179dd4c1823f4969cee0b0515
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>