Convert CONFIG_SPL_GPIO_SUPPORT to Kconfig

configs/sama5d4_xplained_mmc_defconfig

configs/sama5d4_xplained_nandflash_defconfig

configs/sama5d4_xplained_spiflash_defconfig

configs/sama5d4ek_mmc_defconfig

configs/sama5d4ek_nandflash_defconfig

configs/sama5d4ek_spiflash_defconfig

configs/sansa_fuze_plus_defconfig

configs/sc_sps_1_defconfig

configs/smartweb_defconfig

configs/taurus_defconfig

configs/thuban_defconfig

configs/ti814x_evm_defconfig

configs/ti816x_evm_defconfig

configs/udoo_defconfig

configs/wandboard_defconfig

configs/woodburn_sd_defconfig

configs/xfi3_defconfig

configs/xpress_spl_defconfig

configs/zc5202_defconfig

configs/zc5601_defconfig