omap1: LCD_DMA: Use some define rather than a hexadecimal

The patch corrects the issue introduced with one of my earlier patches:
	OMAP: DMA: Fix omapfb/lcdc on OMAP1510 broken when PM set[1]
as pointed out by OMAP subsystem maintainer.

Applies on top of my prevoius patch:
  OMAP: DMA: move LCD DMA related code from plat-omap to mach-omap1[2]

Tested on Amstrad Delta
Compile tested with omap_generic_2420_defconfig

[1] http://patchwork.kernel.org/patch/57922/
[2] http://patchwork.kernel.org/patch/61952/

Signed-off-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/mach-omap1/lcd_dma.c b/arch/arm/mach-omap1/lcd_dma.c
index 4889514..3be11af 100644
--- a/arch/arm/mach-omap1/lcd_dma.c
+++ b/arch/arm/mach-omap1/lcd_dma.c
@@ -28,6 +28,7 @@
 #include <linux/io.h>
 
 #include <mach/hardware.h>
+#include <mach/lcdc.h>
 #include <plat/dma.h>
 
 int omap_lcd_dma_running(void)
@@ -37,7 +38,7 @@
 	 * when it gets enabled, so assume DMA running if LCD enabled.
 	 */
 	if (cpu_is_omap1510())
-		if (omap_readw(0xfffec000 + 0x00) & (1 << 0))
+		if (omap_readw(OMAP_LCDC_CONTROL) & OMAP_LCDC_CTRL_LCD_EN)
 			return 1;
 
 	/* Check if LCD DMA is running */