LU-12861 libcfs: Cleanup use of bare printk

LU-12861 libcfs: Cleanup use of bare printk

Some users of printk(<LEVEL> "fmt" can be converted to
pr_level("fmt" equivalents

Signed-off-by: Shaun Tancheff <stancheff@cray.com>
Change-Id: I5bb13dfa3538839cfaf81137f3cffd937ce55a92
Reviewed-on: https://review.whamcloud.com/37046
Reviewed-by: Ben Evans <bevans@cray.com>
Reviewed-by: Petros Koutoupis <pkoutoupis@cray.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>