boards/qemu-armv7a: revises kernel build sample config

This adjusts `qemu-armv7a:knsh` with following changes:

- use smaller flash/memory so that `-m 1024` can be omitted.
- use ELF_EXECUTABLE for apps to allow easier app debugging.
- enable graceful shutdown from NSH command.
- enable more cases of ostest (e.g. vfork, pthread_exit etc).

Signed-off-by: Yanfeng Liu <p-liuyanfeng9@xiaomi.com>

boards/arm/qemu/qemu-armv7a/configs/knsh/defconfig

@@ -22,14 +22,17 @@ CONFIG_ARCH_INTERRUPTSTACK=2048
 CONFIG_ARCH_KERNEL_STACKSIZE=3072
 CONFIG_ARCH_LOWVECTORS=y
 CONFIG_ARCH_PGPOOL_MAPPING=y
-CONFIG_ARCH_PGPOOL_PBASE=0x48000000
-CONFIG_ARCH_PGPOOL_SIZE=134217728
-CONFIG_ARCH_PGPOOL_VBASE=0x48000000
+CONFIG_ARCH_PGPOOL_PBASE=0x40300000
+CONFIG_ARCH_PGPOOL_SIZE=13631488
+CONFIG_ARCH_PGPOOL_VBASE=0x40300000
 CONFIG_ARCH_STACKDUMP=y
 CONFIG_ARCH_TEXT_NPAGES=256
 CONFIG_ARCH_TEXT_VBASE=0x80000000
+CONFIG_ARM_PSCI=y
 CONFIG_ARM_SEMIHOSTING_HOSTFS=y
 CONFIG_ARM_THUMB=y
+CONFIG_BINFMT_ELF_EXECUTABLE=y
+CONFIG_BOARDCTL_POWEROFF=y
 CONFIG_BUILD_KERNEL=y
 CONFIG_DEBUG_ASSERTIONS=y
 CONFIG_DEBUG_FEATURES=y
@@ -39,9 +42,7 @@ CONFIG_DEFAULT_TASK_STACKSIZE=4096
 CONFIG_ELF=y
 CONFIG_EXAMPLES_HELLO=m
 CONFIG_EXPERIMENTAL=y
-CONFIG_FLASH_SIZE=127926272
-CONFIG_FLASH_START=0x00600000
-CONFIG_FLASH_VSTART=0x00600000
+CONFIG_FLASH_SIZE=1048576
 CONFIG_FS_HOSTFS=y
 CONFIG_FS_PROCFS=y
 CONFIG_HAVE_CXX=y
@@ -66,13 +67,15 @@ CONFIG_NSH_READLINE=y
 CONFIG_ONESHOT=y
 CONFIG_PATH_INITIAL="/system/bin"
 CONFIG_PREALLOC_TIMERS=4
-CONFIG_RAM_SIZE=132120576
-CONFIG_RAM_START=0x40200000
-CONFIG_RAM_VSTART=0x40200000
+CONFIG_RAM_SIZE=16777216
+CONFIG_RAM_START=0x40000000
+CONFIG_RAM_VSTART=0x40000000
 CONFIG_RAW_BINARY=y
 CONFIG_READLINE_CMD_HISTORY=y
 CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_HAVE_PARENT=y
 CONFIG_SCHED_LPWORK=y
+CONFIG_SCHED_WAITPID=y
 CONFIG_STACK_COLORATION=y
 CONFIG_START_DAY=25
 CONFIG_START_MONTH=4