msm: mdss: Remove sysfs for unused commands

Signed-off-by: flar2 <asegaert@gmail.com>
msm: mdss: Identify white point in sysfs

Signed-off-by: flar2 <asegaert@gmail.com>
msm: mdss: Add safety check for user input

Leave more checks either to the control app or the user's intelligence.

Signed-off-by: flar2 <asegaert@gmail.com>