staging: rtlwifi: move remaining phydm .h files

The rtl8188eu driver uses the phydm .h files from the rtlwifi driver,
but now that the rtlwifi driver is gone, it's silly to have a whole
directory for just 2 .h files.  So move these files into the rtl8188eu
driver's directory so that it can be self-contained.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>