swim: Release memory region after incorrect return/goto

The code uses

	return foo;
	goto err_type;

when instead the form should have been

	ret = foo;
	goto err_type;

Here this causes a useful release_mem_region to be skipped.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Laurent Vivier <Laurent@Vivier.EU>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>