When switching from mission mode to FTM or Epping mode, g_pktlog_pde is not cleared after de-init. When switching back to mission mode, a warning is produced as the proc directory is not found. To fix this, g_pktlog_pde is cleared when pktlog is de-initialized. Change-Id: I1b9c9259c220a1981151dcb1e44a5621d7fd8204 CRs-Fixed: 2872045