drivers: apanic_mmc: write panic information to raw MMC partition

This patch is created based on the following changes:

* (CR) apanic_mmc: support writing panic data to
  raw MMC partition
  Reviewed-on: http://gerrit.pcs.mot.com/342283

* (CR): fix no apanic_threads issue
  Reviewed-on: http://gerrit.pcs.mot.com/377655

* (CR) Porting omap split apanic_threads to qcom
  Reviewed-on: http://gerrit.pcs.mot.com/377659

* (CR): Support apanic dump ftrace buffer no
  more than 512k
  Reviewed-on: http://gerrit.pcs.mot.com/377664

* (CR): port apanic annotations from AP20
  Reviewed-on: http://gerrit.pcs.mot.com/392744

* (CR): apanic: add read support to user space
  annotations
  Reviewed-on: http://gerrit.pcs.mot.com/400182

* (CR) Fix potential watchdog reset on emmc kernel
  panic failure for qcom platform.
  Reviewed-on: http://gerrit.pcs.mot.com/404849



Change-Id: Ice455ee53448f05d6d252ab4378963d1cbd01443
Signed-off-by: Yi-wei Zhao <gbjc64@motorola.com>
Reviewed-on: http://gerrit.pcs.mot.com/503768


Tested-by: Jira Key <JIRAKEY@motorola.com>
Reviewed-by: Jason Hrycay <jason.hrycay@motorola.com>
(cherry picked from commit eeef74de)
Signed-off-by: Jeffrey Carlyle <jeff.carlyle@motorola.com>