spl: Kconfig: Rename SPL_USBETH_SUPPORT to SPL_USB_ETHER to match with the U-boot CONFIG

Rename CONFIG_SPL_USBETH_SUPPORT to CONFIG_SPL_USB_ETHER.

This enables users to block text using CONFIG_IS_ENABLED() instead
of resorting to #if ladders with SPL and non-SPL cases.

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
diff --git a/configs/am335x_evm_usbspl_defconfig b/configs/am335x_evm_usbspl_defconfig
index d61aa94..e4bf757 100644
--- a/configs/am335x_evm_usbspl_defconfig
+++ b/configs/am335x_evm_usbspl_defconfig
@@ -15,7 +15,7 @@
 CONFIG_SPL_NET_VCI_STRING="AM335x U-Boot SPL"
 CONFIG_SPL_OS_BOOT=y
 CONFIG_SPL_USB_GADGET_SUPPORT=y
-CONFIG_SPL_USBETH_SUPPORT=y
+CONFIG_SPL_USB_ETHER=y
 # CONFIG_SPL_YMODEM_SUPPORT is not set
 CONFIG_FASTBOOT=y
 CONFIG_CMD_SPL=y
diff --git a/configs/am43xx_hs_evm_defconfig b/configs/am43xx_hs_evm_defconfig
index 170d7c0..b69d855 100644
--- a/configs/am43xx_hs_evm_defconfig
+++ b/configs/am43xx_hs_evm_defconfig
@@ -26,7 +26,7 @@
 CONFIG_SPL_USB_HOST_SUPPORT=y
 CONFIG_SPL_USB_SUPPORT=y
 CONFIG_SPL_USB_GADGET_SUPPORT=y
-CONFIG_SPL_USBETH_SUPPORT=y
+CONFIG_SPL_USB_ETHER=y
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_NAND=y
 # CONFIG_CMD_SETEXPR is not set
diff --git a/configs/mx6memcal_defconfig b/configs/mx6memcal_defconfig
index bf0b4f2..fdcef6b 100644
--- a/configs/mx6memcal_defconfig
+++ b/configs/mx6memcal_defconfig
@@ -12,7 +12,7 @@
 CONFIG_SPL=y
 CONFIG_SPL_USB_HOST_SUPPORT=y
 CONFIG_SPL_USB_GADGET_SUPPORT=y
-CONFIG_SPL_USBETH_SUPPORT=y
+CONFIG_SPL_USB_ETHER=y
 CONFIG_SPL_USB_SDP_SUPPORT=y
 CONFIG_HUSH_PARSER=y
 # CONFIG_CMD_BOOTD is not set