as-z80: djnz label over 1 byte fails to compile

[vbmacher]

ORG 45000
DL: LD IX,0
DJNZ DL

does not compile:

[line=9, column=0, file=/home/vbmacher/tmp/emuStudio/ss.asm] Expression (2 bytes) is bigger than expected (1 byte(s))
Compiling has finished.