drm/amdgpu: device: fix spellos and punctuation

drm/amdgpu: device: fix spellos and punctuation

Make spelling and punctuation changes to ease reading of the comments.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Xinhui Pan <Xinhui.Pan@amd.com>
Cc: amd-gfx@lists.freedesktop.org
Cc: David Airlie <airlied@gmail.com>
Cc: Simona Vetter <simona@ffwll.ch>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>