zram: rename init_lock to dev_lock

[blktests-ci]

Pull request for series with
subject: zram: rename init_lock to dev_lock
version: 1
url: https://patchwork.kernel.org/project/linux-block/list/?series=1042670

[blktests-ci]

Upstream branch: d267c4e
series: https://patchwork.kernel.org/project/linux-block/list/?series=1042670
version: 1

Pull request is NOT updated. Failed to apply https://patchwork.kernel.org/project/linux-block/list/?series=1042670
error message:

Cmd('git') failed due to: exit code(128)
  cmdline: git am --3way
  stdout: 'Applying: zram: rename init_lock to dev_lock
Patch failed at 0001 zram: rename init_lock to dev_lock'
  stderr: 'error: sha1 information is lacking or useless (drivers/block/zram/zram_drv.c).
error: could not build fake ancestor
hint: Use 'git am --show-current-patch=diff' to see the failed patch
hint: When you have resolved this problem, run "git am --continue".
hint: If you prefer to skip this patch, run "git am --skip" instead.
hint: To restore the original branch and stop patching, run "git am --abort".
hint: Disable this message with "git config set advice.mergeConflict false"'

conflict: