drm/amdgpu: Fix do not add new typedefs in amdgpu_fw_attestation.c

Fixes the following to align to coding style:

WARNING: do not add new typedefs
+typedef struct FW_ATT_DB_HEADER

WARNING: do not add new typedefs
+typedef struct FW_ATT_RECORD

WARNING: Symbolic permissions 'S_IRUSR' are not preferred. Consider using octal permissions '0400'.
+                           S_IRUSR,

ERROR: "(foo*)" should be "(foo *)"
WARNING: please, no space before tabs

Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>