amdgpu: add initial support for navy flounder

A new GPU from AMD.

From internal git commit:
5a333628689f142376b8c5b7187f1cf0a8d5abac
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Josh Boyer <jwboyer@kernel.org>

WHENCE

@@ -2477,6 +2477,18 @@ File: amdgpu/green_sardine_rlc.bin
 File: amdgpu/green_sardine_sdma.bin
 File: amdgpu/green_sardine_ta.bin
 File: amdgpu/green_sardine_vcn.bin
+File: amdgpu/navy_flounder_ce.bin
+File: amdgpu/navy_flounder_dmcub.bin
+File: amdgpu/navy_flounder_me.bin
+File: amdgpu/navy_flounder_mec.bin
+File: amdgpu/navy_flounder_mec2.bin
+File: amdgpu/navy_flounder_pfp.bin
+File: amdgpu/navy_flounder_rlc.bin
+File: amdgpu/navy_flounder_sdma.bin
+File: amdgpu/navy_flounder_smc.bin
+File: amdgpu/navy_flounder_sos.bin
+File: amdgpu/navy_flounder_ta.bin
+File: amdgpu/navy_flounder_vcn.bin
 
 Licence: Redistributable. See LICENSE.amdgpu for details.