ACPI / LPSS: provide con_id for the clkdev

Commit 7d78cbefaa (serial: 8250_dw: add ability to handle
the peripheral clock) introduces handling for a second clk
to 8250_dw.c which is the driver also for LPSS UART. The
second clk forces us to provide identifier (con_id) for the
clkdev we create.

This fixes an issue where 8250_dw.c is getting the same
handler for both clocks.

Fixes: 7d78cbefaa (serial: 8250_dw: add ability to handle the peripheral clock)
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: 3.17+ <stable@vger.kernel.org> # 3.17+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/acpi_lpss.c

@@ -65,6 +65,7 @@ struct lpss_private_data;
 
 struct lpss_device_desc {
 	unsigned int flags;
+	const char *clk_con_id;
 	unsigned int prv_offset;
 	size_t prv_size_override;
 	void (*setup)(struct lpss_private_data *pdata);
@@ -140,6 +141,7 @@ static struct lpss_device_desc lpt_i2c_dev_desc = {
 
 static struct lpss_device_desc lpt_uart_dev_desc = {
 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
+	.clk_con_id = "baudclk",
 	.prv_offset = 0x800,
 	.setup = lpss_uart_setup,
 };
@@ -156,6 +158,7 @@ static struct lpss_device_desc byt_pwm_dev_desc = {
 
 static struct lpss_device_desc byt_uart_dev_desc = {
 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
+	.clk_con_id = "baudclk",
 	.prv_offset = 0x800,
 	.setup = lpss_uart_setup,
 };
@@ -313,7 +316,7 @@ out:
 		return PTR_ERR(clk);
 
 	pdata->clk = clk;
-	clk_register_clkdev(clk, NULL, devname);
+	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
 	return 0;
 }