drm/amd/display: Fix a test dml32_rq_dlg_get_rq_reg()

It is likely p1_min_meta_chunk_bytes was expected here, instead of
min_meta_chunk_bytes.

Test the correct variable.

Fixes: dda4fb85 ("drm/amd/display: DML changes for DCN32/321")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>