add /proc/fs_cache to display vnode, path cache, page cache.
also change some bad virable name

close: #I3WESD
Signed-off-by: Nmucor <mucorwang@gmail.com>

1.remove redundant headfile in kernel, such as:
  compiler.h;debug.h;automount.h;inode.h;syslog.h;net.h;
2.split fs.h to file.h and driver.h
3.move vnode.h and path_cache.h to vfs/include
4.remove redundant interface and defines

close: #I3RTNR
Signed-off-by: Nmucor <mucorwang@gmail.com>

support turn off as many features as possible.
current only libc and posix and bsd can not be turned off.
Signed-off-by: NCaoruihong <crh.cao@huawei.com>
Change-Id: I1e97570c67593207a56dc11f357eca4b4a018bfd

Change-Id: I8662952ac9d7912aaf2e2e72f779b3def41d14c4

Change-Id: I052d930d54e63179b17b77f02c107a015f3cfc3f

Change-Id: I5ca037ef20eb65578b804e314617953bfbf6c35b

Description:Delete VM to support only kernel mode.
Sig:liteos_a
Feature or Bugfix:Feature
Binary Source:No

Change-Id: Ie1029c8fbc0c1b85c138663933118d2d148b7769

Change-Id: I608a6e18aad240c52398d744191f6df4bdd68cb5

Feature or Bugfix:Feature
Binary Source:Huawei
PrivateCode(Yes/No):Yes

Change-Id: I175d2648bc6f9078c34de2c0a5c93fda10b86c47
ChangeID:13306388

Change-Id: Ia6c1f6302407a707b3ec9b805f4c92d8a7970b86