media: dvb: symbol fixup for dvb_attach() - again

In commit cd98086a ("media: dvb: symbol fixup for dvb_attach()") in
the 4.14.y tree, a few symbols were missed due to files being renamed in
newer kernel versions.  Fix this up by properly marking up the
sp8870_attach and xc2028_attach symbols.

Reported-by: Ben Hutchings <ben@decadent.org.uk>
Link: https://lore.kernel.org/r/b12435b2311ada131db05d3cf195b4b5d87708eb.camel@decadent.org.uk


Fixes: cd98086a ("media: dvb: symbol fixup for dvb_attach()")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>