drm/amd/display: Fix invalid context error in dml helper

In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Fix invalid context error in dml helper

[Why]

"BUG: sleeping function called from invalid context" error.

after:

"drm/amd/display: Protect FPU in dml2_validate()/dml21_validate()"

The populate_dml_plane_cfg_from_plane_state() uses the GFP_KERNEL flag

for memory allocation, which shouldn't be used in atomic contexts.

The allocation is needed only for using another helper function

get_scaler_data_for_plane().

[How]

Modify helpers to pass a pointer to scaler_data within existing context,

eliminating the need for dynamic memory allocation/deallocation

and copying.

(cherry picked from commit bd3e84bc98f81b44f2c43936bdadc3241d654259)