Revert erronously pushed series of commits, which should not be.

Sorry for the mess.

Revert "sys/vnode.h: remove stale comment"
This reverts commit f193f5a749b696e6c05fa2c47c24522b1624b1a7.

Revert "vfs: convert VFS_OPs from macros to static inlines"
This reverts commit 48bf024f2ef5afeba3500bd92a04283370479edf.

Revert "vnode: add VIRF_KNOTE flag"
This reverts commit 7fe74a02764e5899b10cdc45ab34182b961d5d19.

Revert "vfs: convert vfs_op_thread_* macros to static inlines"
This reverts commit a61a696e78a967b149a6e39b1f98ada26217a6bb.

Revert "struct vnode: assign v_rl.resv1 as v_vrflag"
This reverts commit d990e8f0e9478194569ba28c366b0c0c0f414e7b.

Revert "sys/rangelock.h: explicitly enumerate padding at the end of the structure"
This reverts commit a770638ecf16515d8922111c3fdd417aba6c045e.

Revert "bufspace_wait(): only try to help bufdaemon if there is a chance to help"
This reverts commit 067cfac2e7bd9dc857fb6cc504c01b0249bcd1b7.

Revert "Add O_SYMLINK emulation"
This reverts commit f9458655e78f6532e962a13d28d6a6086b4156de.

Revert "libc: add freadlink(3)"
This reverts commit ae6a13deb8e33a52188643e09171207e1d7171e8.

Revert "Add O_SYMLINK emulation"
This reverts commit 2213820b6f4cd22bbfdc0f45741c3e7d17ae82c0.