x86: coreboot: kconfig: Imply drivers that are useful

U-Boot as coreboot payload can run on any x86 hardware ideally.
Let's imply some common drivers that are useful.
Signed-off-by: NBin Meng <bmeng.cn@gmail.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>

arch/x86/cpu/coreboot/Kconfig

@@ -3,6 +3,16 @@ if TARGET_COREBOOT
 config SYS_COREBOOT
 	bool
 	default y
+	imply ENV_IS_NOWHERE
+	imply E1000
+	imply ICH_SPI
+	imply MMC
+	imply MMC_PCI
+	imply MMC_SDHCI
+	imply MMC_SDHCI_SDMA
+	imply SPI_FLASH
+	imply SYS_NS16550
+	imply VIDEO_COREBOOT
 	imply CMD_CBFS
 	imply FS_CBFS
 

configs/coreboot-x86_defconfig

@@ -4,7 +4,6 @@ CONFIG_TARGET_COREBOOT=y
 CONFIG_FIT=y
 CONFIG_BOOTSTAGE=y
 CONFIG_BOOTSTAGE_REPORT=y
-CONFIG_ENV_IS_NOWHERE=y
 CONFIG_SYS_CONSOLE_INFO_QUIET=y
 CONFIG_HUSH_PARSER=y
 # CONFIG_CMD_IMLS is not set
@@ -32,15 +31,11 @@ CONFIG_ISO_PARTITION=y
 CONFIG_EFI_PARTITION=y
 CONFIG_REGMAP=y
 CONFIG_SYSCON=y
-CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_GIGADEVICE=y
 CONFIG_SPI_FLASH_MACRONIX=y
 CONFIG_SPI_FLASH_WINBOND=y
-CONFIG_E1000=y
-CONFIG_SYS_NS16550=y
 CONFIG_TPM_TIS_LPC=y
 CONFIG_USB_STORAGE=y
 CONFIG_USB_KEYBOARD=y
-CONFIG_VIDEO_COREBOOT=y
 CONFIG_CONSOLE_SCROLL_LINES=5
 CONFIG_TPM=y