patch 8.1.0452: MS-Windows: not finding intl.dll

Problem:    MS-Windows: not finding intl.dll.
Solution:   Also find intl.dll next to libintl.dll. (Ken Takata)
diff --git a/runtime/doc/mlang.txt b/runtime/doc/mlang.txt
index 4d85bbd..f25aef2 100644
--- a/runtime/doc/mlang.txt
+++ b/runtime/doc/mlang.txt
@@ -102,8 +102,10 @@
 
 This also contains tools xgettext, msgformat and others.
 
-libintl.dll should be placed in same directory with (g)vim.exe, or some
-place where PATH environment value describe.  Vim also finds libintl-8.dll.
+libintl.dll should be placed in same directory as (g)vim.exe, or one of the
+directories listed in the PATH environment value.  Vim also looks for the
+alternate names "libintl-8.dll" and "intl.dll".
+
 Message files (vim.mo) have to be placed in "$VIMRUNTIME/lang/xx/LC_MESSAGES",
 where "xx" is the abbreviation of the language (mostly two letters).