Add the SNR monitoring for the dib7000p. The result is in dB.
Signed-off-by: NOlivier Grenie <olivier.grenie@dibcom.fr>
Signed-off-by: NPatrick Boettcher <patrick.boettcher@dibcom.fr>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>