serial/imx: get rid of the uses of cpu_is_mx1()

The patch removes all the uses of cpu_is_mx1().  Instead, it uses
the .id_table of platform_driver to distinguish the uart device type,
IMX1_UART and IMX21_UART.  The IMX21_UART type runs on all i.mx
except i.mx1.

A couple of !cpu_is_mx1 logic gets turned into is_imx21_uart,
as the codes wrapped there are really IMX21 type uart specific.

It also removes macro MX1_UCR3_REF25 and MX1_UCR3_REF30 which are
not used anywhere.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/arch/arm/mach-mx5/clock-mx51-mx53.c b/arch/arm/mach-mx5/clock-mx51-mx53.c
index 23cd809..b8119e8 100644
--- a/arch/arm/mach-mx5/clock-mx51-mx53.c
+++ b/arch/arm/mach-mx5/clock-mx51-mx53.c
@@ -1422,9 +1422,10 @@
        },
 
 static struct clk_lookup mx51_lookups[] = {
-	_REGISTER_CLOCK("imx-uart.0", NULL, uart1_clk)
-	_REGISTER_CLOCK("imx-uart.1", NULL, uart2_clk)
-	_REGISTER_CLOCK("imx-uart.2", NULL, uart3_clk)
+	/* i.mx51 has the i.mx21 type uart */
+	_REGISTER_CLOCK("imx21-uart.0", NULL, uart1_clk)
+	_REGISTER_CLOCK("imx21-uart.1", NULL, uart2_clk)
+	_REGISTER_CLOCK("imx21-uart.2", NULL, uart3_clk)
 	_REGISTER_CLOCK(NULL, "gpt", gpt_clk)
 	_REGISTER_CLOCK("fec.0", NULL, fec_clk)
 	_REGISTER_CLOCK("mxc_pwm.0", "pwm", pwm1_clk)
@@ -1470,11 +1471,12 @@
 };
 
 static struct clk_lookup mx53_lookups[] = {
-	_REGISTER_CLOCK("imx-uart.0", NULL, uart1_clk)
-	_REGISTER_CLOCK("imx-uart.1", NULL, uart2_clk)
-	_REGISTER_CLOCK("imx-uart.2", NULL, uart3_clk)
-	_REGISTER_CLOCK("imx-uart.3", NULL, uart4_clk)
-	_REGISTER_CLOCK("imx-uart.4", NULL, uart5_clk)
+	/* i.mx53 has the i.mx21 type uart */
+	_REGISTER_CLOCK("imx21-uart.0", NULL, uart1_clk)
+	_REGISTER_CLOCK("imx21-uart.1", NULL, uart2_clk)
+	_REGISTER_CLOCK("imx21-uart.2", NULL, uart3_clk)
+	_REGISTER_CLOCK("imx21-uart.3", NULL, uart4_clk)
+	_REGISTER_CLOCK("imx21-uart.4", NULL, uart5_clk)
 	_REGISTER_CLOCK(NULL, "gpt", gpt_clk)
 	_REGISTER_CLOCK("fec.0", NULL, fec_clk)
 	_REGISTER_CLOCK(NULL, "iim_clk", iim_clk)