binary_codes_writer.c: simplify control flow
binary_codes_writer.c: simplify control flow

Also, avoid uninitialized intermediate variable.

Change-Id: I9e9e1e816ae0c9f0ec664b7f7d3ca75a7a22c995

GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom