Staging: hv: Zero out the request structure on allocation

As part of the cleanup of the I/O request structure, allocate them zeroed
out. This fixes a bug that was introduced in the patch-set titled:
Staging: hv: Cleanup-storage-drivers-phase-II.
A corrected version of this patch-set was sent out earlier, however
the earlier (buggy) version of this patch-set was already applied.
This patch fixes the problem.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Hank Janssen <hjanssen@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/hv/storvsc_drv.c

@@ -738,7 +738,7 @@ static int storvsc_queuecommand_lck(struct scsi_cmnd *scmnd,
 
 	request_size = sizeof(struct storvsc_cmd_request);
 
-	cmd_request = kmem_cache_alloc(host_device_ctx->request_pool,
+	cmd_request = kmem_cache_zalloc(host_device_ctx->request_pool,
 				       GFP_ATOMIC);
 	if (!cmd_request) {
 		DPRINT_ERR(STORVSC_DRV, "scmnd (%p) - unable to allocate "