Refactor to invoke only one GetBestLanguage()

(based on FatPkg commit 25e83a4e8906ef80e428b7c446216faa1ba9e2a7)

[jordan.l.justen@intel.com: Use script to relicense to 2-clause BSD]
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Acked-by: Mark Doran <mark.doran@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>

FatPkg/EnhancedFatDxe/UnicodeCollation.c

@@ -87,23 +87,13 @@ InitializeUnicodeCollationSupportWorker (
     // Find the best matching matching language from the supported languages
     // of Unicode Collation (2) protocol. 
     //
-    if (Language == NULL) {
     BestLanguage = GetBestLanguage (
                      Uci->SupportedLanguages,
                      Iso639Language,
+                     (Language == NULL) ? Language : "",
                      DefaultLanguage,
                      NULL
                      );
-    } else {
-      BestLanguage = GetBestLanguage (
-                       Uci->SupportedLanguages,
-                       Iso639Language,
-                       Language,
-                       Iso639Language,
-                       DefaultLanguage,
-                       NULL
-                       );
-    }
     if (BestLanguage != NULL) {
       FreePool (BestLanguage);
       mUnicodeCollationInterface = Uci;