postprocess: remove unneeded FBDD enforcement for convert

If convert is used with dcraw (instead of dcraw_emu), then dcraw
reports error:

    1: No such file or directory

Convert doesn't use '$@' (-fbdd 1), so there is no reason to enforce
it here. postprocess.sh already detects  dcraw
version (dcraw/dcraw_emu) and sets FBDD option. FBDD is supported only
by dcraw_emu.

Fixes: 8867b41a (Support graphicsmagick as alternative to imagemagick)

data/postprocess.sh

@@ -65,8 +65,6 @@ CONVERT=""
 if command -v "convert" > /dev/null
 then
 	CONVERT="convert"
-	# -fbdd 1	Raw denoising with FBDD
-	set -- -fbdd 1
 elif command -v "gm" > /dev/null
 then
 	CONVERT="gm"