drm/amd/display: Reduce number of arguments of dcn30's CalculatePrefetchSchedule()

drm/amd/display: Reduce number of arguments of dcn30's CalculatePrefetchSchedule()

After an innocuous optimization change in clang-22,
dml30_ModeSupportAndSystemConfigurationFull() is over the 2048 byte
stack limit for display_mode_vba_30.c.

  drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn30/display_mode_vba_30.c:3529:6: warning: stack frame size (2096) exceeds limit (2048) in 'dml30_ModeSupportAndSystemConfigurationFull' [-Wframe-larger-than]
   3529 | void dml30_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_lib)
        |      ^

With clang-21, this function was already close to the limit:

  drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn30/display_mode_vba_30.c:3529:6: warning: stack frame size (1912) exceeds limit (1586) in 'dml30_ModeSupportAndSystemConfigurationFull' [-Wframe-larger-than]
   3529 | void dml30_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_lib)
        |      ^

CalculatePrefetchSchedule() has a large number of parameters, which must
be passed on the stack. Most of the parameters between the two callsites
are the same, so they can be accessed through the existing mode_lib
pointer, instead of being passed as explicit arguments. Doing this
reduces the stack size of dml30_ModeSupportAndSystemConfigurationFull()
from 2096 bytes to 1912 bytes with clang-22.

Closes: https://github.com/ClangBuiltLinux/linux/issues/2117
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>