[MAX9A][96724][CPHY] ppr value set 3 or 4 cause max9a detection fail

[randylintw]

kernel log
[ 5.455069] IPU ACPI: SSDB: name INTC031M:00. link 0. lanes 4. pprval 3. pprunit 4. degree 180

9.386069] [494] max9x 2-0027: CSI link 0: enabled=1, num_lanes=4, freq_mhz=2000, init_deskew=1
[ 9.386073] [494] max9x 2-0027: CSI link 1: enabled=0, num_lanes=0, freq_mhz=0, init_deskew=0
[ 9.386074] [494] max9x 2-0027: CSI link 2: enabled=0, num_lanes=0, freq_mhz=0, init_deskew=0
[ 9.386076] [494] max9x 2-0027: CSI link 3: enabled=0, num_lanes=0, freq_mhz=0, init_deskew=0
[ 9.386078] max9x 2-0027: Invalid CSI configuration! Supported modes: 4x2, 2x4, 1x4+2x2, 2x2+1x4
[ 9.396615] max9x 2-0027: Failed to enable

Maybe update the doc to avoid confusing with D-PHY.