m68k: Avoid pointless recursion in debug console rendering

m68k: Avoid pointless recursion in debug console rendering

The recursive call to console_putc to effect a carriage return is
needlessly slow and complicated. Instead, just clear the column counter
directly. Setup %a0 earlier to avoid a repeated comparison.

Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Tested-by: Stan Johnson <userm57@yahoo.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/a6104f41918bed4fd17f92c45df94ac7a5d30e40.1743115195.git.fthain@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>