Cleanup uboot handling like linux kernel

buildroot-external/board/raspberrypi/rpi/uboot.config

@@ -1,3 +0,0 @@
-CONFIG_TARGET_RPI=y
-CONFIG_DEFAULT_DEVICE_TREE="bcm2835-rpi-b"
-CONFIG_SYS_TEXT_BASE=0x00008000

buildroot-external/board/raspberrypi/rpi0-w/uboot.config

@@ -1,3 +0,0 @@
-CONFIG_TARGET_RPI_0_W=y
-CONFIG_DEFAULT_DEVICE_TREE="bcm2835-rpi-zero-w"
-CONFIG_SYS_TEXT_BASE=0x00008000

buildroot-external/board/raspberrypi/rpi2/uboot.config

@@ -1,4 +0,0 @@
-CONFIG_TARGET_RPI_2=y
-CONFIG_DEFAULT_DEVICE_TREE="bcm2836-rpi-2-b"
-CONFIG_SYS_TEXT_BASE=0x00008000
-CONFIG_SYS_TEXT_BASE=0x00008000

buildroot-external/board/raspberrypi/rpi3-64/uboot.config

@@ -1,6 +0,0 @@
-CONFIG_TARGET_RPI_3=y
-CONFIG_SYS_MALLOC_F_LEN=0x2000
-CONFIG_SYS_TEXT_BASE=0x00080000
-CONFIG_DEFAULT_DEVICE_TREE="bcm2837-rpi-3-b"
-CONFIG_PHYLIB=y
-CONFIG_USB_ETHER_LAN78XX=y

buildroot-external/board/raspberrypi/rpi3/uboot.config

@@ -1,6 +0,0 @@
-CONFIG_TARGET_RPI_3_32B=y
-CONFIG_SYS_MALLOC_F_LEN=0x2000
-CONFIG_SYS_TEXT_BASE=0x00008000
-CONFIG_DEFAULT_DEVICE_TREE="bcm2837-rpi-3-b"
-CONFIG_PHYLIB=y
-CONFIG_USB_ETHER_LAN78XX=y

buildroot-external/board/raspberrypi/uboot.config

@@ -1,24 +1,3 @@
-CONFIG_ARM=y
-CONFIG_ARCH_BCM283X=y
-CONFIG_OF_BOARD_SETUP=y
-# CONFIG_CMD_FLASH is not set
-CONFIG_CMD_GPIO=y
-CONFIG_CMD_MMC=y
-CONFIG_CMD_USB=y
-CONFIG_OF_EMBED=y
-CONFIG_DM_KEYBOARD=y
-CONFIG_DM_MMC=y
-CONFIG_MMC_SDHCI=y
-CONFIG_MMC_SDHCI_BCM2835=y
-CONFIG_DM_ETH=y
-CONFIG_PINCTRL=y
-# CONFIG_PINCTRL_GENERIC is not set
-# CONFIG_REQUIRE_SERIAL_CONSOLE is not set
-CONFIG_USB=y
-CONFIG_DM_USB=y
-CONFIG_USB_DWC2=y
-CONFIG_USB_KEYBOARD=y
-CONFIG_USB_HOST_ETHER=y
-CONFIG_USB_ETHER_SMSC95XX=y
-CONFIG_DM_VIDEO=y
-CONFIG_PHYS_TO_BUS=y
+# CONFIG_USB_STORAGE is not set
+# CONFIG_ENV_FAT_INTERFACE is not set
+# CONFIG_ENV_FAT_DEVICE_AND_PART is not set