msm_fb: HDMI: Fix EDID parsing logic for multiple data blocks

This change fixes a bug in EDID parsing logic when there are
more than one data blocks of the same type in the EDID data. With
this change, the starting offset used to scan for the next data
block, is computed correctly.

Change-Id: I5d09fe61be9f7c749197991f54e430ae3aaddbcb
Signed-off-by: Aravind Venkateswaran <aravindh@codeaurora.org>