goldfish: pipe: fix warnings for 32bit builds

drivers/platform/goldfish/goldfish_pipe.c: In function 'goldfish_cmd_status':
drivers/platform/goldfish/goldfish_pipe.c:164:14: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
writel((u32)(u64)pipe, dev->base + PIPE_REG_CHANNEL);
^
drivers/platform/goldfish/goldfish_pipe.c: In function 'goldfish_cmd':
drivers/platform/goldfish/goldfish_pipe.c:180:14: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
writel((u32)(u64)pipe, dev->base + PIPE_REG_CHANNEL);
^
drivers/platform/goldfish/goldfish_pipe.c: In function 'goldfish_pipe_read_write':
drivers/platform/goldfish/goldfish_pipe.c:337:16: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
writel((u32)(u64)pipe, dev->base + PIPE_REG_CHANNEL);

Reported-by: Fengguang Wu <[e-mail]>
Cc: Jun Tian <[e-mail]>
Acked-by: Alan Cox <[e-mail]>
Signed-off-by: Octavian Purdila <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/platform/goldfish/goldfish_pipe.c

···
 	struct goldfish_pipe_dev *dev = pipe->dev;
 
 	spin_lock_irqsave(&dev->lock, flags);
-	gf_write64((u64)pipe, dev->base + PIPE_REG_CHANNEL,
+	gf_write64((u64)(unsigned long)pipe, dev->base + PIPE_REG_CHANNEL,
 				dev->base + PIPE_REG_CHANNEL_HIGH);
 	writel(cmd, dev->base + PIPE_REG_COMMAND);
 	status = readl(dev->base + PIPE_REG_STATUS);
···
 	struct goldfish_pipe_dev *dev = pipe->dev;
 
 	spin_lock_irqsave(&dev->lock, flags);
-	gf_write64((u64)pipe, dev->base + PIPE_REG_CHANNEL,
+	gf_write64((u64)(unsigned long)pipe, dev->base + PIPE_REG_CHANNEL,
 				dev->base + PIPE_REG_CHANNEL_HIGH);
 	writel(cmd, dev->base + PIPE_REG_COMMAND);
 	spin_unlock_irqrestore(&dev->lock, flags);
···
 		spin_lock_irqsave(&dev->lock, irq_flags);
 		if (access_with_param(dev, CMD_WRITE_BUFFER + cmd_offset,
 				address, avail, pipe, &status)) {
-			gf_write64((u64)pipe, dev->base + PIPE_REG_CHANNEL,
-					dev->base + PIPE_REG_CHANNEL_HIGH);
+			gf_write64((u64)(unsigned long)pipe,
+				   dev->base + PIPE_REG_CHANNEL,
+				   dev->base + PIPE_REG_CHANNEL_HIGH);
 			writel(avail, dev->base + PIPE_REG_SIZE);
 			gf_write64(address, dev->base + PIPE_REG_ADDRESS,
 				dev->base + PIPE_REG_ADDRESS_HIGH);