lcd: supposed vlock_m and vlock_farc interface [1/1]

lcd: supposed vlock_m and vlock_farc interface [1/1]

PD#TV-3683

Problem:
Repeatedly exit HDMI channel cause black screen

Solution:
1, support vlock_m and vlock_frac interface
2, optimized clk change and de timing

Verify:
verify on t962x2-x301

Change-Id: Iddedade08300290853e59b026b3ca1b9939eed79
Signed-off-by: shaochan.liu <shaochan.liu@amlogic.com>