core: fix parsing quoted paramers in To header

- fix off-by-one bug for quoted parameter values in parse_to
- patch by Alex Hermann, SF#3035382
(cherry picked from commit 8593bc83c748835c6132eaa678064a2466316ae7)

parser/parse_to.c

@@ -246,7 +246,7 @@ static /*inline*/ char* parse_to_param(char *buffer, char *end,
 						status = PARA_VALUE_QUOTED;
 						break;
 					case PARA_VALUE_QUOTED:
-						param->value.len=tmp-param->value.s-1 ;
+						param->value.len=tmp-param->value.s;
 						add_param( param , to_b );
 						status = E_PARA_VALUE;
 						break;