Merge pull request !113 from lnlan/musl_issue

【背景】
处理issue，两个无符号数比较大小的方法有问题
【修改方案】
1.由a-b>0修改为a>b的方式

【影响】
对现有的产品编译不会有影响。

re #I48CM3
Signed-off-by: Nlanleinan <lanleinan@163.com>
Change-Id: I93bf5e603ca3f257e44a023e9814fd4d7d5004ae

Merge pull request !112 from Zachery Wu/zzzuo

Signed-off-by: NZachery Wu <wuzuoyu@huawei.com>
Change-Id: I4cfbf06e7cdfb45137df91d3626019255a4caaf1

Merge pull request !103 from lnlan/rm_unsupport

Merge pull request !105 from dhy308/master

Merge pull request !95 from Caoruihong/reduce_mod

【背景】
getaddrinfo和freeaddrinfo已经支持，去除unsupport打印
【修改方案】
getaddrinfo和freeaddrinfo已经支持，去除unsupport打印
【影响】
对现有的产品编译不会有影响。

re #I296BH
Signed-off-by: Nlanleinan <lanleinan@163.com>
Change-Id: Ia00ece3c75c8f83394fadda9c90578a937fcd786

Signed-off-by: Ndhy308 <tony.gan@huawei.com>

	new file:   porting/linux/user/src/thread/arm/syscall_cp.s

Merge pull request !67 from x_xiny/master

Merge pull request !96 from guweijie/gwj-musl-ppoll-20210825

Merge pull request !97 from wangjianjun/sys

Merge pull request !86 from wangjianjun/waitid

Merge pull request !87 from wcc/fs

【背景】L0 需要新增适配posix接口

【修改方案】
 新增 L0 posix接口

 re #I42IQY
Signed-off-by: Nx-xiny <1301913191@qq.com>

Change-Id: I5c3faf8ea00f9c6bb2713e84321bc368e4abbd14

去掉porting下的冗余文件

Change-Id: I08ae64da75f7765e5801e1470b03a42e2504d5b5
Signed-off-by: Nwjj <502004968@qq.com>

1.modifications:
deleted:    porting/liteos_a/user/src/linux/ppoll.c
2.influence:
none
Signed-off-by: Nteamol <28105285@qq.com>

Signed-off-by: NCaoruihong <crh.cao@huawei.com>
Change-Id: Ie225b037aba2eb233a7d2a53566cdb11d902c5ee

Merge pull request !93 from dhy308/master

Signed-off-by: Ndhy308 <tony.gan@huawei.com>

Merge pull request !92 from dhy308/master

Merge pull request !91 from Caoruihong/update_musl

Merge pull request !91 from Caoruihong/update_musl

Signed-off-by: NCaoruihong <crh.cao@huawei.com>
Change-Id: I36ed85c6af3b80f780f26c047e096fe861b9e8c3

Signed-off-by: Ndhy308 <tony.gan@huawei.com>

Merge pull request !90 from dhy308/master

Merge pull request !88 from zhushengle/exit

Signed-off-by: Ndhy308 <tony.gan@huawei.com>

Merge pull request !77 from phchang/fixsync

问题描述：
    进程在退出过程中，拿到了init_fini_lock锁后被信号打断，
收到退出信号，再次调用exit函数进入进程退出流程，造成死锁

解决方案：
    在libc中添加exit字段，在进程退出时将该字段表示进程已经在退出，
若再次进入退出流程，则直接退出，由第一个执行退出流程的线程继续执行
退出流程。并且在退出时屏蔽信号，避免退出流程被频繁打断。
Close #I43V23
Signed-off-by: Nzhushengle <zhushengle@huawei.com>

Change-Id: I57b60391267d50c8eb89fc115a26229461bb4ed4

Merge pull request !84 from give-me-five/master

add fchdir and testcases

Change-Id: Idb62087ddc46b3b7db4ceaef478d7b9192115628
Signed-off-by: Nwcc0 <917033401@qq.com>

删除porting下的冗余文件

Change-Id: Ib9541b3f34c6b8020727829e16578c283aea8bc3
Signed-off-by: Nwjj <502004968@qq.com>

Change-Id: Ieb45066f200d0da1d28367ec4fac2e9c33378dc5
Signed-off-by: Nsilen <wuyunjie@huawei.com>

Merge pull request !69 from MGY917/cloexec

Merge pull request !81 from zhuoli72/master

Merge pull request !80 from Zhaotianyu/0731libc_opt

Merge pull request !72 from wcc/fstatfs

!52 fix mutex&pthread mould musl api:pthread_mutexattr_getrobust/pthread_mutexattr_setrobust/pthread_mutex_consistent/pthread_getconcurrency/pthread_setconcurrency
Merge pull request !52 from 王建军/mutex

针对字符串类高频函数：
1. 采用单次多字节操作提升字符串类高频函数的执行效率
2. 针对armv7-a，采用neon指令进行优化

close: #I42DAK

Change-Id: I6d09a549436a1130da71d79274d38be86f156199
Signed-off-by: Narvinzzz <zhaotianyu9@huawei.com>