libdvbv5: get rid of dvb-scan-table-handler.[ch]

libdvbv5: get rid of dvb-scan-table-handler.[ch]

those files were useful during the transition to use the
descriptors library. However, after all code changes, they
became too tiny, and dependent of dvb-scan.[ch]. So, merge
the code and header back into them.

Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>