Fix a potential bug in LLImageDimensionsInfo where mWidth was being set to...

Fix a potential bug in LLImageDimensionsInfo where mWidth was being set to width and width was never set.

indra/llimage/llimagedimensionsinfo.cpp

@@ -203,7 +203,7 @@ bool LLImageDimensionsInfo::getImageDimensionsJpeg()
 	cinfo.out_color_space = JCS_RGB;
 	jpeg_start_decompress	(&cinfo);
 
-	mHeight = cinfo.output_width;
+	mWidth = cinfo.output_width;
 	mHeight = cinfo.output_height;
 
 	jpeg_destroy_decompress(&cinfo);