resolve-host: make arg_type an int

We are using it also to store _DNS_TYPE_INVALID, so it should be signed.

src/resolve/dns-type.c

@@ -32,16 +32,14 @@ lookup_dns_type (register const char *str, register unsigned int len);
 #include "dns_type-from-name.h"
 #include "dns_type-to-name.h"
 
-int dns_type_from_string(const char *s, uint16_t *type) {
+int dns_type_from_string(const char *s) {
         const struct dns_type_name *sc;
 
         assert(s);
-        assert(type);
 
         sc = lookup_dns_type(s, strlen(s));
         if (!sc)
-                return -EINVAL;
+                return _DNS_TYPE_INVALID;
 
-        *type = sc->id;
-        return 0;
+        return sc->id;
 }

src/resolve/dns-type.h

@@ -21,12 +21,10 @@
 
 #pragma once
 
-#include <inttypes.h>
-
 #include "macro.h"
 
-const char *dns_type_to_string(uint16_t type);
-int dns_type_from_string(const char *s, uint16_t *type);
+const char *dns_type_to_string(int type);
+int dns_type_from_string(const char *s);
 
 /* DNS record types, taken from
  * http://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml.