agetty: when logname is erased, re-enable reloads

When user starts to enter logname, 8b58ffdd blocks issue reloads.
Reloads remain blocked even if user deletes all typed characters.

Make things visually consistent: If no characters are entered,
re-enable reloads.

Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
Signed-off-by: Karel Zak <kzak@redhat.com>
Reviewed-by: Lubomir Rintel <lkundrak@v3.sk>
Tested-by: Lubomir Rintel <lkundrak@v3.sk>

term-utils/agetty.c

@@ -2182,6 +2182,9 @@ static char *get_logname(struct issue *ie, struct options *op, struct termios *t
 				*bp++ = ascval;			/* and store it */
 				break;
 			}
+			/* Everything was erased. */
+			if (bp == logname)
+				goto no_reload;
 		}
 	}