Kconfig: Rename CONFIG_SPL_DMA_SUPPORT to CONFIG_SPL_DMA

Rename CONFIG_SPL_DMA_SUPPORT to CONFIG_SPL_DMA. This allows to use
macros such as CONFIG_IS_ENABLED() that allow conditional compilation of
code for SPL and U-Boot.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/imx28_xea_defconfig b/configs/imx28_xea_defconfig
index aaa7e31..c7a1e15 100644
--- a/configs/imx28_xea_defconfig
+++ b/configs/imx28_xea_defconfig
@@ -24,7 +24,7 @@
 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR=y
 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR=0
 CONFIG_SUPPORT_EMMC_BOOT_OVERRIDE_PART_CONFIG=y
-CONFIG_SPL_DMA_SUPPORT=y
+CONFIG_SPL_DMA=y
 CONFIG_SPL_DM_GPIO=y
 CONFIG_SPL_FORCE_MMC_BOOT=y
 CONFIG_SPL_MMC_TINY=y