build: avoid AM_CONDITIONAL in conditional execution.

Automake does not support conditional AM_CONDITIONAL calls; what that
means is that you always have to execute AM_CONDITIONAL one way or the
other. Both the libsqlite3.m4 file and the nfsdcld conditionals are
executed only when NFSv4 is enabled, which breaks building with
--disable-nfsv4.

Remove the SQLite3 conditional altogether as it's never used, and move
the nfsdcld conditional outside of the conditional code.

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Diego Elio Pettenò <flameeyes@flameeyes.eu>
Signed-off-by: Steve Dickson <steved@redhat.com>