[i386] Rename __cdecl to __asmcall

__cdecl is a misleading name, since it currently encapsulates both
cdecl and regparm(0) attributes.  Rename to __asmcall.

src/core/main.c

@@ -34,7 +34,7 @@ static struct feature features_end[0] __table_end ( struct feature, features );
  *
  * @ret rc		Return status code
  */
-__cdecl int main ( void ) {
+__asmcall int main ( void ) {
 	struct feature *feature;
 
 	initialise();