--auto-mode can result in an infinite loop

[Summertime]

Generally this seems to be possible with any JPEG file after repeatedly running

jpegoptim -v -m 80 --auto-mode file.jpg

Image quality limit set to: 80
Using maximum of 1 parallel threads
file.jpg 658x881 24bit N Exif,JFIF,ICC [OK] (retry w/progressive) 153443 --> 106748 bytes (30.43%), optimized.


jpegoptim -v -m 80 --auto-mode file.jpg 

Image quality limit set to: 80
Using maximum of 1 parallel threads
file.jpg 658x881 24bit P JFIF,Exif,ICC [OK] (retry w/normal) (revert to progressive) (retry w/lossless) (retry w/normal) (revert to progressive) (retry w/lossless) (retry w/normal) (revert to progressive) # repeat forever