drm/amd/display: Modify header inclusion pattern

[Why]
Recent backport from opensource broke the Nightly tool build
that tests DC and DML for bugs and regressions. This was
because the backport had a header inclusion that was not
consistent with the AMD style of including headers was allowed
to be merged back in DML code that caused tool compilation
failures.

[How]
Modify the way in which the header file in included so that it
is consistent with AMD style of including headers. This then
automatically fixes the tool compilation process and also
helps maintain the code quality and consistency.

Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Brian Chang <Brian.Chang@amd.com>
Signed-off-by: Chaitanya Dhere <chaitanya.dhere@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>