rootfs改为300M

buildroot-external/configs/ark1668e_devb_emmc_defconfig

@@ -55,7 +55,7 @@ BR2_PACKAGE_WPA_SUPPLICANT_PASSPHRASE=y
 BR2_PACKAGE_ANDROID_TOOLS=y
 BR2_TARGET_ROOTFS_EXT2=y
 BR2_TARGET_ROOTFS_EXT2_4=y
-BR2_TARGET_ROOTFS_EXT2_SIZE="500M"
+BR2_TARGET_ROOTFS_EXT2_SIZE="300M"
 # BR2_TARGET_ROOTFS_TAR is not set
 BR2_PACKAGE_LIBARKAPI=y
 BR2_LIBARKAPI_ARK1668E=y