[USB]fix rt_usbd_set_config() BUG which set the USB device to configuration state before enumerating the device.
[libcpu/arm] remove useless cpsr updating in rt_hw_context_switch_to

This piece of code will enable the interrupt early before switching to
the first thread. Although it is harmless, but not prefect.
[bsp/rva8] enable group{0,1} interrupt forwarding in gic initialization

When RT-Thread is running stand alone, it forgot to enable the
distributor of GIC.
Merge pull request #256 from grissiom/qemu-realview-vmm

Qemu realview vmm
[shell] define FINSH_PROMPT as finsh_get_prompt when FINSH_USING_MSH enabled

When MSH enabled, the prompt will change at the two shells. So we should
use dynamic prompt when FINSH_USING_MSH defined.
Merge pull request #257 from grissiom/fix-shell

[shell] define FINSH_PROMPT as finsh_get_prompt when FINSH_USING_MSH enabled
MSH: perfect cmd ifconfig.
MSH: add cmd netstat.
Merge pull request #258 from aozima/pulls

update MSH ifconfig and add MSH netstat.
scons: seperate the BSP build with the kernel build

BSPs could have their own components/ etc. If they point to the same
folder, SCons would find the wrong source code to compile.
scons: no need to set RTT_ROOT as Repository

In SCons manual:

=================
In order to inform the C compiler about the repositories,  SCons will
add appropriate -I flags to the compilation commands for each directory
in the $CPPPATH list. So if we add the current directory to the
construction environment $CPPPATH like so:

    env = Environment(CPPPATH = ['.'])
    env.Program('hello.c')
    Repository('/usr/repository1')

Then re-executing SCons yields:

    % scons -Q
    cc -o hello.o -c -I. -I/usr/repository1 hello.c
    cc -o hello hello.o
=================

The additional include directory is definitely not what we want. Just
remove the additional Repository line.
Merge pull request #254 from weety/Branch_usb

[USB]fix rt_usbd_set_config() BUG which set the USB device to configurat...
logtrace: add const modifier to the APIs

Compiler may do more optimization when the parameter is const.
logtrace: add log_session_lvl

log_session_lvl is suitable for performance critical places where in
most cases, the log is turned off by level. If the session is const and
the level is greater than session->lvl, the whole function will be
optimized out.
Merge pull request #260 from grissiom/logtrace-next

Logtrace next
Merge pull request #259 from grissiom/fix-scons

Fix scons