src: Use virStrcpyStatic() wherever possible

src: Use virStrcpyStatic() wherever possible

This convenience macro was created for the simple cases
where the length of the source string and the size of the
destination buffer can be figued out with strlen() and
sizeof() respectively, so we should use it wherever
possible instead of open-coding parts of it.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>