Revert "Revert "Revert "kernel: Move REPEAT_BYTE definition into linux/kernel.h"""

This reverts commit 44c5f074b1ab6d6d202cf5bdd60330c83dce07b6.
Revert "word-at-a-time: make the interfaces truly generic"

This reverts commit f8e95a3e048495f3c7aa81c421a657db954549fe.
Revert "lib: Sparc's strncpy_from_user is generic enough, move under lib/"

This reverts commit bff3f70718aa5d1ae8a648a04b0fa29a721903f1.
Revert "lib: add generic strnlen_user() function"

This reverts commit dbd48a523b214636ee89bb2d3113e5a05ad62622.
Revert "ARM: use generic strnlen_user and strncpy_from_user functions"

This reverts commit 62a449bafe3c59d07b07f0ffe4683ff1efb2d851.