drm: atmel_hlcdc: Add support for XLCDC using IP specific driver ops

Add XLCDC specific driver ops and is_xlcdc flag to separate the
functionality and to access the controller registers.
HEO scaling, window resampling, Alpha blending, YUV-to-RGB
conversion in XLCDC is derived and handled using additional
configuration bits and registers. Writing one to the Enable fields
of each layer in LCD_ATTRE is required to reflect the values set
in Configuration, FBA, Enable registers of each layer.

Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
Co-developed-by: Hari Prasath Gujulan Elango <Hari.PrasathGE@microchip.com>
Signed-off-by: Hari Prasath Gujulan Elango <Hari.PrasathGE@microchip.com>
Co-developed-by: Durai Manickam KR <durai.manickamkr@microchip.com>
Signed-off-by: Durai Manickam KR <durai.manickamkr@microchip.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240424053351.589830-5-manikandan.m@microchip.com