configs: get rid of build warnings due to SPL_USB_DWC3_GENERIC

Adding the SPL_USB_DWC3_GENERIC symbol broke some ti builds. This
should fix the builds but untested on HW.

Signed-off-by: Angus Ainslie <angus@akkea.ca>
diff --git a/configs/dra7xx_evm_defconfig b/configs/dra7xx_evm_defconfig
index bd3ce11..935e353 100644
--- a/configs/dra7xx_evm_defconfig
+++ b/configs/dra7xx_evm_defconfig
@@ -10,6 +10,7 @@
 CONFIG_OMAP54XX=y
 CONFIG_TARGET_DRA7XX_EVM=y
 CONFIG_SPL=y
+CONFIG_SPL_MISC=y
 CONFIG_ENV_OFFSET_REDUND=0x280000
 CONFIG_SPL_SPI_FLASH_SUPPORT=y
 CONFIG_SPL_SPI=y
@@ -147,6 +148,7 @@
 CONFIG_USB_DWC3=y
 CONFIG_USB_DWC3_OMAP=y
 CONFIG_USB_DWC3_GENERIC=y
+CONFIG_SPL_USB_DWC3_GENERIC=y
 CONFIG_USB_DWC3_PHY_OMAP=y
 CONFIG_USB_GADGET=y
 CONFIG_USB_GADGET_MANUFACTURER="Texas Instruments"