python3-magic: add the missing rdepends

Add the missing rdepends to fix below error:
 # python3
 [snip]
 >>> import magic
 [snip]
 ModuleNotFoundError: No module named 'ctypes'
 ModuleNotFoundError: No module named 'tempfile'

Signed-off-by: Mingli Yu <mingli.yu@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit 11579184)
Signed-off-by: Steve Sakoman <steve@sakoman.com>