intel_reg_read: add a flag to simplify bit decoding

intel_reg_read: add a flag to simplify bit decoding

This allows to specify '-d' parameter which will decode individual bits in
each register being read.

The register bits are printed horizontally for space reasons. This
requires more than 80x25 terminal to see them all. An alternative solution
would be to print them vertically, but this will become much more
difficult to read when printing multiple registers at the same time.

v2: fix spacing to get us a bit closer to the code nirvana.

Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>