[sanitizer] Remove #include <linux/fs.h> to resolve...

[sanitizer] Remove #include <linux/fs.h> to resolve fsconfig_command/mount_attr conflict with glibc 2.36

It is generally not a good idea to mix usage of glibc headers and Linux UAPI
headers (https://sourceware.org/glibc/wiki/Synchronizing_Headers). In glibc
since 7eae6a91e9b1670330c9f15730082c91c0b1d570 (milestone: 2.36), sys/mount.h
defines `fsconfig_command` which conflicts with linux/mount.h:

    .../usr/include/linux/mount.h:95:6: error: redeclaration of ‘enum fsconfig_command’

Remove #include <linux/fs.h> which pulls in linux/mount.h. Expand its 4 macros manually.

Fix https://github.com/llvm/llvm-project/issues/56421

Reviewed By: #sanitizers, vitalybuka, zatrazz

Differential Revision: https://reviews.llvm.org/D129471