msm: mdss: Edit MDP sysfs node text layout

Display kernel driver uses a sysfs node for outputting MDP capabilities.
This data needs to be written in a proper format. Editing the
current format to have a single keyword instead of spaces. Also,
using an "equal to" sign instead of colon.

Change-Id: I2d2b71f27194cc50bfe1b7395cc0910896f499f4
Signed-off-by: Shalabh Jain <shalabhj@codeaurora.org>