wrbmp.c, wrtarga.c: Remove unused variables

(should have been done with the previous commit)

wrbmp.c

@@ -436,7 +436,6 @@ finish_output_bmp(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
   JSAMPARRAY image_ptr;
   register JSAMPROW data_ptr;
   JDIMENSION row;
-  register JDIMENSION col;
   cd_progress_ptr progress = (cd_progress_ptr)cinfo->progress;
 
   if (dest->use_inversion_array) {

wrtarga.c

@@ -118,7 +118,6 @@ put_gray_rows(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
   tga_dest_ptr dest = (tga_dest_ptr)dinfo;
   register JSAMPROW inptr;
   register char *outptr;
-  register JDIMENSION col;
 
   inptr = dest->pub.buffer[0];
   outptr = dest->iobuffer;