diag: Proper update of logging mode

The patch properly updates the logging mode after an user PD
on-device logging session is killed preventing a mutex deadlock
and thereby safe ODL session clearing.

CRs-Fixed: 2154183
Change-Id: I8451ed3869f5b75860684d5ef4119befd0cb2723
Signed-off-by: Manoj Prabhu B <bmanoj@codeaurora.org>