ARM: OMAP: dma: Make use of cpu_class_is_omap2() to avoid future patching.

cpu_class_is_omap2() contains all OMAP2+ devices. So update the DMA code
cpu checks accordingly so that there is no need to patch
the file for any future OMAP2+ devices.

In long run, all these attributes should come from hwmod dev_attr based
on DMA IP version.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
index ecdb3da..c046a19 100644
--- a/arch/arm/plat-omap/dma.c
+++ b/arch/arm/plat-omap/dma.c
@@ -843,7 +843,7 @@
 	}
 	l = p->dma_read(CCR, lch);
 	l &= ~((1 << 6) | (1 << 26));
-	if (cpu_is_omap2430() || cpu_is_omap34xx() ||  cpu_is_omap44xx())
+	if (cpu_class_is_omap2() && !cpu_is_omap242x())
 		l |= ((read_prio & 0x1) << 6) | ((write_prio & 0x1) << 26);
 	else
 		l |= ((read_prio & 0x1) << 6);
@@ -2057,7 +2057,7 @@
 		}
 	}
 
-	if (cpu_is_omap2430() || cpu_is_omap34xx() || cpu_is_omap44xx())
+	if (cpu_class_is_omap2() && !cpu_is_omap242x())
 		omap_dma_set_global_params(DMA_DEFAULT_ARB_RATE,
 				DMA_DEFAULT_FIFO_DEPTH, 0);