PM / devfreq: memlat: Use the cpumask_pr_args macros

When using the %*pbl printk format a special macro is needed to decode
the cpu mask and format it correctly.

Fixes: 74b58a68 ("PM / devfreq: memlat: Aggregate memlat mons under a controller")
Change-Id: Ic0dedbada86cf9cec02b1a5292aaf05f50c0c42f
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>