Strip trailing whitespace, reference decoder source (Atch 1)

Change-Id: I7a7970ebd0253a2c8d62fe6e988c4a8d3f7a2227
modified:   text_src/atch1/dixie_loopfilter.c
modified:   text_src/atch1/vp8_prob_data.h
modified:   text_src/atch1/vpx_decoder.h
modified:   text_src/atch1/vpx_decoder_compat.h
modified:   text_src/atch1/vpx_image.h