cmake: enable CMP0046

cmake: enable CMP0046

so cmake will error on "non-existent dependency in add_dependencies", we
add dependency on CONFIGURE_FILE() output, which is wrong, as its output
is not a target, and is generated when cmake runs. so remove them from
dependencies.

regarding to ceph_ver.h, its path is also wrong. it is created under
${CMAKE_BINARY_DIR}/src/include. so this is another reason to remove it.

Signed-off-by: Kefu Chai <kchai@redhat.com>