STM32F4系列UART在初始化的时候，如果GPIO_AF放到GPIO_INIT后边，系统复位后，串口会向外发送一个字节的数据，通常是0x00。将GPIO_AF放到GPIO_INIT前边可以避开这个问题。

1. upddate kernel module to support i386
2. update libdl to support open *.so by absolute path
3. new test case bsp/x86/src/hello.c to test i386 module feature
Signed-off-by: Nparai <parai@foxmail.com>

Signed-off-by: NParai Wang <parai@foxmail.com>

currently only read okay, write is not supported, this is enough for
me to study ELF, but the floppy is really small, now only about 400kb
space free showed by df("/").
Signed-off-by: Nparai <parai@foxmail.com>

most of the code copy from tinix, just make it run, code quality is not good.
Signed-off-by: Nparai <parai@foxmail.com>

[bsp] Prevent compilation errors in bxcan.c when using STM32F10X_LD_VL,STM32F10X_MD_VL,STM32F10X_HD_VL incorrectly choose to use the RT_USING_CAN.

[bsp] Fix a CAN interrupt number macro definition bug for STM32F10X_LD,STM32F10X_MD and STM32F10X_XL series.

    fixed error when enable "SPI2_USING_DMA"
    fixed warnning when using spi without DMA

remove unused line in SConstruct

modify：     ../../libcpu/risc-v/e310/stack.c
	rmove unused macro definition
modify：     ../../src/idle.c
	Return to the original version

	add file that forget to submit before
	auto change timer mtimercmp register on the base of RT_TICK_PER_SECOND in rtconfig.h
	no flashing led
new file：   ../../src/idle.c
	recover old file

	save mie into stack
msh  running normaly

change interrupt num to 53
change stack size to 512 before system starup
add uart drivers
open msh
remain bug:
   uart just interrupt ones

	save sp to old thread
	clear rt_thread_switch_interrupt_flag
always enable interrupt after rt_hw_context_switch
judeg the type of interrupt in trap_entry, then call handler(Machine timer interrupt of Machine external interrupt)

	enable interrupt after return form rt_hw_context_switch