drm/amd/pm: Clean up errors in amdgpu_smu.c

Fix the following errors reported by checkpatch:

ERROR: spaces required around that '=' (ctx:WxV)
ERROR: spaces required around that '&&' (ctx:VxW)
ERROR: that open brace { should be on the previous line
ERROR: space required before the open parenthesis '('
ERROR: space required before the open brace '{'
ERROR: spaces required around that ':' (ctx:VxW)

Signed-off-by: Ran Sun <sunran001@208suo.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>