mipi_dsi: modify printk message

[matsujirushi]

I changed code comments and printk messages only.

Test environment:

• reTerminal 06/09/21
• STM32 firmware v1.9
• Raspberry Pi OS bookwarm 64bit

  Raspberry Pi reference 2023-10-10
  Generated using pi-gen, https://github.com/RPi-Distro/pi-gen, 962bf483c8f326405794827cce8c0313fd5880a8, stage4

dmesg:

$ dmesg | grep mipi
[    7.295511] mipi_dsi: Initialize kernel module
[    7.295537] mipi_dsi: (i2c_md_init) Add I2C driver
[    7.295689] mipi_dsi: Probe I2C driver
[    7.295701] mipi_dsi: (i2c_md_probe) Start
[    7.307029] mipi_dsi: Add MIPI-DSI device to device tree
[    7.307321] mipi_dsi: (i2c_md_probe) Add panel
[    7.307948] mipi_dsi: (backlight_init) Register backlight device
[    7.308072] mipi_dsi: (backlight_update) brightness=255
[    7.311454] mipi_dsi: (i2c_md_probe) Finish
[    7.311999] mipi_dsi: (i2c_md_init) Register MIPI-DSI driver
[    7.312072] mipi_dsi: Probe MIPI-DSI driver
[    7.579274] mipi_dsi: Prepare panel
[    7.676123] mipi_dsi: Prepare ILI9881D
[    7.823927] mipi_dsi: Enable panel
[    9.719939] mipi_dsi: (backlight_update) brightness=255

[bigbearishappy]

Thank you for your contribution. Please update the code mentioned below.

[matsujirushi]

@bigbearishappy Thank you for review. I updated.