Convert CONFIG_CMD_PCI to Kconfig

This converts the following to Kconfig:
   CONFIG_CMD_PCI

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
diff --git a/configs/ls1021atwr_sdcard_ifc_SECURE_BOOT_defconfig b/configs/ls1021atwr_sdcard_ifc_SECURE_BOOT_defconfig
index 3ac0595..c37271d 100644
--- a/configs/ls1021atwr_sdcard_ifc_SECURE_BOOT_defconfig
+++ b/configs/ls1021atwr_sdcard_ifc_SECURE_BOOT_defconfig
@@ -31,8 +31,8 @@
 CONFIG_CMD_MEMTEST=y
 CONFIG_CMD_MEMINFO=y
 CONFIG_CMD_GPT=y
-CONFIG_CMD_MMC=y
 CONFIG_CMD_I2C=y
+CONFIG_CMD_MMC=y
 CONFIG_CMD_USB=y
 CONFIG_CMD_BMP=y
 # CONFIG_SPL_EFI_PARTITION is not set