Add a few simple tests for getting the root node, since this is handled
as a special case in the implementation.

Signed-off-by: Simon Glass <sjg@chromium.org>

Add support for writing a single 64-bit value into a property.

Repurpose the existing tests to handle this case too.

Signed-off-by: Simon Glass <sjg@chromium.org>

Add functions to write a boolean property. This involves deleting it if
the value is false.

Add a new ofnode_has_property() as well. Add a comment about the behaviour
of of_read_property() when the property value is empty.

Signed-off-by: Simon Glass <sjg@chromium.org>

Add a way to flatten a devicetree into binary form. For livetree this
involves generating the devicetree using fdt_property() and other calls.
For flattree it simply involves providing the buffer containing the tree.

Signed-off-by: Simon Glass <sjg@chromium.org>

Add a function to delete a node in an existing tree.

Signed-off-by: Simon Glass <sjg@chromium.org>

Add a function to copy a node to another place under a new name. This is
useful at least for testing, since copying a test node with existing
properties is easier than writing the code to generate it all afresh.

Signed-off-by: Simon Glass <sjg@chromium.org>

Provide a function to create a new, empty tree.

Signed-off-by: Simon Glass <sjg@chromium.org>

Add comments to the functions where the test name does not indicate what
is being tested. Rename functions in a few cases, so that a search for the
function will also file its test.

Signed-off-by: Simon Glass <sjg@chromium.org>

We need the UT_TESTF_SCAN_FDT flag set for these tests to run with flat
tree. In some cases it is missing, so add it.

Signed-off-by: Simon Glass <sjg@chromium.org>

Follow the order used by memcpy() as it may be less confusing.

Signed-off-by: Simon Glass <sjg@chromium.org>