drm/amdgpu: Don't use UTS_RELEASE directly

drm/amdgpu: Don't use UTS_RELEASE directly

UTS_RELEASE evaluates to a static string and changes quite easily (e.g.
uncommitted changes in the source tree or new commits). So when checking
if a patch introduces changes to the resulting binary each usage of
UTS_RELEASE is source of annoyance.

Instead of using UTS_RELEASE directly use init_utsname()->release which
evaluates to the same string but with that a change of UTS_RELEASE
doesn't affect amdgpu_dev_coredump.o.

Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Uwe Kleine-König (The Capable Hub) <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/20260428144704.1114562-2-u.kleine-koenig@baylibre.com
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit d785df5598fd1d1cc2f2f45c05448271b6d490b7)