patch 8.1.0743: giving error messages is not flexible

Problem:    Giving error messages is not flexible.
Solution:   Add semsg().  Change argument from "char_u *" to "char *", also
            for msg() and get rid of most MSG macros. (Ozaki Kiichi, closes
            #3302)  Also make emsg() accept a "char *" argument.  Get rid of
            an enormous number of type casts.
diff --git a/src/farsi.h b/src/farsi.h
index db6bda6..33f1974 100644
--- a/src/farsi.h
+++ b/src/farsi.h
@@ -203,7 +203,7 @@
 #endif
 		     ;
 
-EXTERN char_u farsi_text_3[]
+EXTERN char farsi_text_3[]
 #ifdef DO_INIT
 		= { DAL, WAW, _SHIN, _YE, _MIM, _NOON, ' ', YE_, _NOON,
 		    ALEF_,_BE, _YE, _TE, _SHIN, _PE, ' ', 'R','E','P','L',