debian: Remove pam_systemd.so from common-session

Remove pam_systemd.so from /etc/pam.d/common-session
since it was causing a performance hit with mtcClient
running at the same time.

Test Plan on Debian:
PASS: package build, image build
PASS: system installation, bootstrap and unlock
PASS: console login by sysadmin. Observed that home
      directory is created the first time the user login.
PASS: su to sysdmin. Observed that home
      directory is created the first time the user is su to.
PASS: wait for timeout, log back in, and run
      system host-unlock controller-0
PASS: check for systemd --user processes.

Story: 2009965
Task: 45290

Signed-off-by: Charles Short <charles.short@windriver.com>
Change-Id: Ida555ade017ddebd50fc02d703f177026c498957

pam-config/source-debian/common-session

@@ -19,4 +19,3 @@ session     required        pam_permit.so
 session     [success=1 new_authtok_reqd=done default=ignore]    pam_unix.so
 session     [success=ok new_authtok_reqd=done default=bad]      pam_sss.so
 session     required        pam_mkhomedir.so umask=0022 skel=/etc/skel
-session     optional        pam_systemd.so