* Fix picker and list mode conflict

* Comment the change

Co-authored-by: Todd Yamakawa <todd.yamakawa@arm.com>

* Unvectorize xstrlcpy

On all libcs I could find, memcpy does a better job than we can.

* Rename xstrlcpy to xstrsncpy to avoid confusion

The semantics of our xstrlcpy differed slightly from strlcpy; we return
the number of copied characters; strlcpy returns the strlen(src).
strscpy from Linux is similar except it returns the number of copied
characters sans the NUL byte, so this is named strsncpy to be different.