add QEMU arm 'virt' CFI flash support, enable rootfs and user-space app

tools/build/config/debug/qemu_arm_virt_ca7_clang.config

@@ -34,6 +34,7 @@ LOSCFG_ARCH_CPU="cortex-a7"
 #
 # LOSCFG_ARCH_FPU_DISABLE is not set
 LOSCFG_IRQ_USE_STANDALONE_STACK=y
+LOSCFG_PLATFORM_ROOTFS=y
 
 #
 # Kernel
@@ -43,7 +44,7 @@ LOSCFG_KERNEL_EXTKERNEL=y
 # LOSCFG_KERNEL_CPPSUPPORT is not set
 LOSCFG_KERNEL_CPUP=y
 LOSCFG_CPUP_INCLUDE_IRQ=y
-# LOSCFG_KERNEL_DYNLOAD is not set
+LOSCFG_KERNEL_DYNLOAD=y
 # LOSCFG_KERNEL_VDSO is not set
 # LOSCFG_KERNEL_TICKLESS is not set
 # LOSCFG_KERNEL_TRACE is not set
@@ -72,7 +73,7 @@ LOSCFG_FILE_MODE=y
 # LOSCFG_FS_FAT is not set
 LOSCFG_FS_RAMFS=y
 LOSCFG_FS_PROC=y
-# LOSCFG_FS_JFFS is not set
+LOSCFG_FS_JFFS=y
 
 #
 # Net
@@ -97,7 +98,7 @@ LOSCFG_SHELL=y
 # LOSCFG_SHELL_LK is not set
 # LOSCFG_SHELL_EXCINFO is not set
 # LOSCFG_EXC_INTERACTION is not set
-# LOSCFG_USER_INIT_DEBUG is not set
+LOSCFG_USER_INIT_DEBUG=y
 # LOSCFG_SHELL_CMD_DEBUG is not set
 # LOSCFG_MEM_DEBUG is not set
 # LOSCFG_NULL_ADDRESS_PROTECT is not set
@@ -125,7 +126,7 @@ LOSCFG_DRIVERS_HDF_PLATFORM=y
 # LOSCFG_DRIVERS_HDF_USB is not set
 LOSCFG_DRIVERS_MEM=y
 # LOSCFG_DRIVERS_MMC is not set
-# LOSCFG_DRIVERS_MTD is not set
+LOSCFG_DRIVERS_MTD=y
 # LOSCFG_DRIVERS_RANDOM is not set
 # LOSCFG_DRIVERS_VIDEO is not set
 # LOSCFG_DRIVERS_HIEVENT is not set