ti: Convert CONFIG_TI_EDMA3 to Kconfig

This converts the following to Kconfig:
   CONFIG_TI_EDMA3

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>
diff --git a/configs/k2g_hs_evm_defconfig b/configs/k2g_hs_evm_defconfig
index fc77d43..ffa41de 100644
--- a/configs/k2g_hs_evm_defconfig
+++ b/configs/k2g_hs_evm_defconfig
@@ -42,6 +42,7 @@
 CONFIG_BOOTP_SEND_HOSTNAME=y
 CONFIG_DM=y
 CONFIG_DFU_MMC=y
+CONFIG_TI_EDMA3=y
 CONFIG_SPL_SYS_I2C_LEGACY=y
 CONFIG_SYS_I2C_DAVINCI=y
 CONFIG_MISC=y