msm: mdss: hdmi: Proper length check for EDID data block

Check for the invalid length of EDID (Extended Display Identification
Data) data blocks while parsing the blocks. For a valid data block,
length should not be zero or should not exceed max size.

Change-Id: I4e83b07689d2c3161048efabbad35a0ad00e371a
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>