imxfb: add support for i.MX25

The commit also introduces the HAVE_FB_IMX config that is to be selected from
the MX25 platform config. Once this commit gets merged, the two other i.MX
archs, ARCH_MX1 and ARCH_MX2, should follow this one.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

arch/arm/plat-mxc/Kconfig

@@ -24,6 +24,7 @@ config ARCH_MX25
 	bool "MX25-based"
 	select CPU_ARM926T
 	select COMMON_CLKDEV
+	select HAVE_FB_IMX
 	help
 	  This enables support for systems based on the Freescale i.MX25 family
 

drivers/video/Kconfig

@@ -400,9 +400,12 @@ config FB_SA1100
 	  If you plan to use the LCD display with your SA-1100 system, say
 	  Y here.
 
+config HAVE_FB_IMX
+	bool
+
 config FB_IMX
 	tristate "Motorola i.MX LCD support"
-	depends on FB && (ARCH_MX1 || ARCH_MX2)
+	depends on FB && (HAVE_FB_IMX || ARCH_MX1 || ARCH_MX2)
 	select FB_CFB_FILLRECT
 	select FB_CFB_COPYAREA
 	select FB_CFB_IMAGEBLIT