drm/amdkfd: Use a new capability bit for SRAM ECC

Existing, buggy user mode breaks when SRAM ECC is correctly reported as
"enabled". To avoid breaking existing user mode, deprecate that bit and
leave it as 0. Define a new bit to report the actual SRAM ECC mode that
new, correct user mode can use in the future.

Fixes: 7ec177bdcfc1 ("drm/amdkfd: fix set kfd node ras properties value")
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Kent Russell <kent.russell@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>