Create /proc/asound/card<card_no>/eld#<codec_no> to reflect the audio
configurations and capabilities of the attached HDMI sink.

Some notes:

- Shall we show an empty file if the ELD content is not valid?
  Well it's not that simple. There could be partially populated ELD,
  and there may be malformed ELD provided by buggy drivers/monitors.
  So expose ELD as it is.

- The ELD retrieval routines rely on the Intel HDA interface,
  others are/could be universal and independent ones.

- How do we name the proc file?
  If there are going to be two HDMI pins per codec, then the current naming
  scheme (eld#<codec no>) will fail. Luckily the user space dependencies should
  be minimal, so it would be trivial to do the rename if that happens.

- The ELD proc file content is designed to be easy for scripts and human reading.
  Its lines all have the pattern:
	  <item_name>\t[\t]*<item_value>
  where <item_name> is a keyword in c language, while <item_value> could be any
  contents, including white spaces. <item_value> could also be a null value.
Signed-off-by: NWu Fengguang <wfg@linux.intel.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

ELD handling routines can be shared by all HDMI codecs,
and they are large enough to make a standalone source file.
Signed-off-by: NWu Fengguang <wfg@linux.intel.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Reorder HDMI audio enabling sequence so that
	1) the sink knows about the coming audio stream
	2) unmute
	3) start transferring audio samples

The theory is that in the path A=>B=>C, we first make C ready, and then
enable B, and lastly allow A to send audio samples.
Signed-off-by: NWu Fengguang <wfg@linux.intel.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Move the handling of SiI1392 HDMI codec from patch_atihdmi.c to
patch_intelhdmi.c, which makes our ASUS P5E-VM HDMI board work.
Signed-off-by: NWu Fengguang <wfg@linux.intel.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Add a proper ifdef to shut out a compile warning:
   CC [M]  sound/pci/hda/patch_intelhdmi.o
sound/pci/hda/patch_intelhdmi.c:286: warning: ‘hdmi_get_dip_index’ defined but \
not used
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Add support for Intel G45 integrated HDMI audio codecs.

This initial release supports:
	- 2 channel stereo sound output
	- report monitor's ELD information
Signed-off-by: NWu Fengguang <wfg@linux.intel.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>