patch 7.4.1065

Problem:    Cannot use the "dll" options on MS-Windows.
Solution:   Support the options on all platforms.  Use the built-in name as
            the default, so that it's clear what Vim is looking for.

src/if_perl.xs

@@ -611,12 +611,7 @@ perl_runtime_link_init(char *libname, int verbose)
 perl_enabled(verbose)
     int		verbose;
 {
-#ifdef WIN3264
-    char *dll = DYNAMIC_PERL_DLL;
-#else
-    char *dll = *p_perldll ? (char *)p_perldll : DYNAMIC_PERL_DLL;
-#endif
-    return perl_runtime_link_init(dll, verbose) == OK;
+    return perl_runtime_link_init((char *)p_perldll, verbose) == OK;
 }
 #endif /* DYNAMIC_PERL */